Laser caps and red light hats for hair loss: the trials, the wavelengths and every partner device reviewed

Q: Do red light hats actually regrow hair?

For pattern hair loss, laser devices raised hair counts more than sham devices in randomized trials, by about 18.6 hairs per cm² on average. The effect is modest, most people in the trials had early to moderate loss, and the trials lasted 16 to 26 weeks. LED-only hats have less evidence: one trial, with a mixed result.

Q: Is a laser cap better than an LED hat?

No trial compares them head to head. Most of the hair evidence comes from lasers, alone or with LEDs, and devices with laser diodes alone showed a larger pooled effect. The one LED-only cap trial found no single cap beat sham.

Q: What wavelength should a hair cap use?

Most trials used red light near 655 nm; one used 630 to 660 nm. Near-infrared (around 808 to 850 nm) has fewer hair studies. Blue light alone did not beat sham in the one trial that tested it; we found no hair trial of green light.

Q: What does FDA-cleared mean for a laser cap?

Cleared through a 510(k): the FDA found the device substantially equivalent to one already sold. It is not FDA approval. Kiierr’s clearance, K181878, says no clinical data were produced for it. You can look up any number on the FDA 510(k) database.

Q: How long until I see results?

The cleared course is 30 minutes every other day for an initial 16 weeks, and the trials measured results at 16 to 26 weeks. Some trials saw temporary shedding in the first 1 to 2 months.

Q: Can I use a laser cap with minoxidil or finasteride?

Two 2025 meta-analyses of laser plus minoxidil disagree on whether it adds anything. We found no randomized trial of a cap with finasteride. Ask your clinician; caps are not a substitute for the approved drugs, which have larger, longer trials.

Q: Do more diodes work better?

Not that the trials show. An analysis across the randomized trials found the number of diodes was not linked to hair gains, while energy per session and total time under the light were.

Q: Who should not use a red light cap?

Talk to a clinician first if you are pregnant, are sensitive to light or take a photosensitizing medicine, have a changing spot on your scalp, or have a pacemaker or other implanted device; the trials excluded these groups. Never look into the diodes.

Q: Is there a Kiierr or Hooga discount?

When we last checked (Oct 16, 2026), arriving through our Hooga link applied a 12% referral discount at checkout, with no code to type. We have no Kiierr discount to offer.

Red-light laser caps raised hair counts against sham devices in randomized trials of pattern hair loss, by a modest amount and mostly in trials run or paid for by device makers. Here is what the trials used, what the wavelengths mean, and how all ten caps, helmets and hats sold by our partners compare, with every FDA record checked.

Devices · Evidence review By Kymata Health Editorial Prices checked Oct 18, 2026 Last checked Oct 18, 2026

We earn a commission if you buy through links on this page. It never changes our grades or rankings. How we make money →

Disclosure: Kiierr, Hooga Health and Happy Head are affiliate partners. Links to them on this page are paid links, and Kymata Health may earn a commission if you buy through them, at no extra cost to you. We have not tested these devices; specs, prices and terms are each brand's own, read on its site on Oct 18, 2026.

The short answer

Hair count vs sham (Grade A)

Yes, modestly, for pattern hair loss.

In sham-controlled trials of men and women with early to moderate pattern hair loss, red-light laser devices raised hair counts more than look-alike sham devices over 16 to 26 weeks. In the largest set of trials, terminal hair density rose by 18.4 to 25.7 hairs per cm² with a laser comb vs 1.6 to 9.4 with a sham¹⁴, and a 2026 meta-analysis put the average gain at 18.56 hairs per cm² over sham²². People often could not tell the difference themselves^13,23, most trials were paid for or run by device makers^12,14,16, the trials ran 26 weeks at most²¹, and no trial compares one brand of cap with another or with finasteride²⁹.

The evidence, graded

4 outcomes

Grade AHair count vs sham, pattern hair lossSham-controlled randomized trials with well over 300 people between them found the same direction of effect^10,14, and so did the meta-analyses that pooled them^19,20,21. The grade is about how much evidence there is, not how good it is: one network meta-analysis rated the laser-vs-sham evidence very low in quality³¹.
Grade CFeeling your hair is betterMixed: more laser-comb users reported improvement in one set of trials¹⁴, but participants did not rate the comb above sham in the Cochrane review²³, and subjects in a helmet trial saw no difference¹³.
Grade CLED-only caps (no lasers)One 160-person trial: no single LED cap beat sham at 16 weeks, and only the pooled caps did, in a per-protocol analysis that left out 91 people¹⁶.
Grade CAdding a laser to minoxidilTwo 2025 meta-analyses disagree: one found 6.62 more hairs per cm² with the combination²⁶, the other no difference²⁷.

Graded on our supplement scale. Grade A: At least two concordant randomized controlled trials (RCTs), or a meta-analysis of RCTs, with a combined total of 300 or more participants. How we grade

How laser caps work, and what the wavelengths mean

Laser caps and red light hats shine low-power red light, and sometimes near-infrared, onto the scalp for a few minutes at a time. This is low-level laser or light therapy (LLLT), also called photobiomodulation. In the caps cleared by the FDA, each laser diode puts out 5 mW or less².

How it might work is still a hypothesis. The leading idea is that cytochrome c oxidase, an enzyme in mitochondria, absorbs the light, which releases nitric oxide that was holding it back and raises ATP production; signals that follow may move resting follicles into the growth phase (anagen)^6,7. A review of the hair evidence calls the main mechanism “hypothesized” and says the best wavelength, coherence and dose “remain to be determined”⁷.

Dose is energy delivered per area, in J/cm²: power density (mW/cm²) multiplied by time. Typical low-level light devices deliver 1 to 10 J/cm² at 3 to 90 mW/cm²⁷. The 2013 and 2014 helmet trials report 67 J/cm² per 25-minute session^11,12. Across the hair trials, more energy per session and more total time under the light went with larger gains; the number of diodes did not²⁴.

The light bands

What the trials used

Light bands: range, how far each reaches, what the hair trials used and which devices here use it
Band	How far it reaches	In the hair trials	Devices on this page
Blue and greenAbout 415–525 nm	How far it reaches: Shorter wavelengths are used for surface tissue⁸	In the hair trials: One LED cap trial tested 425 nm blue light; no single arm beat sham¹⁶	Devices here: Hooga ColorWave hat (415 + 520 nm), Kiierr combs (450 nm)
RedAbout 630–660 nm	How far it reaches: Wavelengths from 600 nm up reach deeper than blue⁸	In the hair trials: Most trials: 655 nm lasers^10,11,14; one helmet used 630, 650 and 660 nm¹³	Devices here: Every cap, helmet and hat on this page
Near-infraredAbout 800–850 nm	How far it reaches: Invisible; the 600–1,100 nm range is used for deeper tissue⁸	In the hair trials: Fewer studies; one meta-analysis that mixed trials with uncontrolled studies found infrared light effective for pattern hair loss²⁵	Devices here: Kiierr DualWave caps (808 nm lasers), Hooga hats (850 nm LEDs)

Laser diodes vs LEDs

No head-to-head trial

Laser diodes compared with LEDs
	Laser diodes	LEDs
The light	Laser diodes: A coherent, collimated, near single-wavelength beam⁹; ± 5 nm in the trial helmets¹¹	LEDs: Not coherent and a broader band, ± 20 nm in the same helmets¹¹; covers a wide area at once⁹
Eye safety	Laser diodes: Class 3R diodes in the cleared caps²: never look into them	LEDs: No laser safety considerations^9,32
Cost	Laser diodes: Higher; caps here run $499 to $2,199	LEDs: Much lower cost per mW⁹; hats here are $299
Hair evidence	Laser diodes: Most sham-controlled hair trials used lasers, alone or with LEDs^10,11,14. Devices with laser diodes alone showed a larger pooled effect than devices that mixed lasers and LEDs²⁰	LEDs: One LED-only cap trial, with a mixed result¹⁶
Head-to-head	Laser diodes: No trial compares a laser cap with an LED cap, or one brand with another²⁹	LEDs: Same

What the trials show

Every randomized trial below compared a real device with a look-alike sham, except the last, which compared it with minoxidil. Results are the authors' own.

The randomized trials

8 trials

Randomized trials of laser and LED devices for pattern hair loss
Trial	Who and how many	Device and schedule	Result	Funding and ties
Leavitt 2009¹⁰	Who: Men, Norwood IIa–Vn = 110 completed (randomized 2:1)	Device: HairMax LaserComb, 9 beams at 655 nm26 weeks	Result: Terminal hair density rose significantly more than with sham (p < 0.0001); no serious adverse events	Funding and ties: Not stated in the abstract
Kim 2013¹³	Who: 40 adults with pattern hair lossn = 40	Device: Helmet, 630, 650 and 660 nm18 min daily, 24 weeks	Result: Greater hair density and hair diameter than sham; investigators saw a difference, subjects did not	Funding and ties: Not stated in the abstract
Lanzafame 2013¹¹	Who: Men 18–48, Norwood IIa–V, skin types I–IVn = 44 (41 completed)	Device: TOPHAT655 helmet: 21 lasers at 655 nm + 30 LEDs25 min every other day, 16 weeks	Result: Hair counts up 67.2% vs 28.4% with sham (P = 0.001); no adverse events	Funding and ties: Same device and team as the 2014 trial
Jimenez 2014 (four trials)¹⁴	Who: 128 men, Norwood IIa–V; 141 women, Ludwig-Savin I-4 to II-2; skin types I–IVn = 269 (225 analysed)	Device: HairMax LaserComb, 7, 9 or 12 beams at 635–655 nm8–15 min, 3 times a week, 26 weeks	Result: Terminal hair density up 18.4 to 25.7 per cm² vs 1.6 to 9.4 with sham; no serious adverse events	Funding and ties: Lexington (HairMax) partly funded the trials and supplied the devices; 94.7% of participants were white
Lanzafame 2014¹²	Who: Women 18–60, Ludwig-Savin I-2 to II-2, skin types I–IVn = 47 (42 completed)	Device: TOPHAT655 helmet: 21 lasers at 655 nm + 30 LEDs25 min every other day, 16 weeks	Result: Hair count in a 2.85 cm² area up 100.3 vs 23.9 with sham (P < 0.0001); no adverse events	Funding and ties: Funded by Apira Science, the device maker; one author has an ownership interest
Suchonwanit 2019¹⁵	Who: 20 men and 20 women, Thailandn = 40 (36 completed)	Device: RAMACAP laser helmet24 weeks	Result: Hair density and diameter better than sham (p = 0.002 and 0.009); temporary shedding and scalp itch reported	Funding and ties: Device developed by the authors’ institute; the authors call their sham inappropriate
Thomas 2025¹⁶	Who: Adults 18–65 with pattern hair lossn = 160 (69 per protocol)	Device: LED cap: 625 + 660 nm red, 425 nm blue, or both10 min daily; primary result at 16 weeks	Result: No single cap beat sham; the three caps pooled gave 28.5 more hairs per cm² than sham (p = .033)	Funding and ties: Several authors work for the device companies (emitBio, KNOW Bio)
Esmat 2017¹⁷	Who: 45 women with female pattern hair lossn = 45	Device: iGrow helmet vs minoxidil 5% vs both; no sham25 min 3 times a week, 4 months	Result: Laser and minoxidil gave comparable results; the combination did best on Ludwig grade and satisfaction	Funding and ties: Not stated in the abstract

Meta-analyses and reviews

7 reviews

Meta-analyses and systematic reviews of laser therapy for pattern hair loss
Review	What it pooled	What it found
Adil & Godwin 2017¹⁸	Pooled: Randomized trials of good or fair quality, men	Found: Laser therapy, minoxidil and finasteride all beat placebo; high heterogeneity
Liu 2019¹⁹	Pooled: 11 double-blind randomized trials	Found: Hair density higher with lasers than sham (SMD 1.316), in both sexes and with combs and helmets; less frequent sessions did better than more frequent ones
Lueangarun 2021²⁰	Pooled: 7 double-blind trials of FDA-cleared home devices	Found: Hair density higher than sham (SMD 1.27); laser diodes alone 1.52 vs 0.85 for devices that combined them with other sources
Cochrane review 2016²³	Pooled: Women: 2 laser-comb trials, 141 people	Found: Hair count up about 17.4 to 17.6 more than sham (low-quality evidence); participants did not rate the comb better than sham
Gupta & Bamimore 2020²⁴	Pooled: Randomized trials of laser therapy for pattern hair loss	Found: More energy per session, more total exposure and pulsed light went with bigger gains; the number of diodes did not
Perez 2025²¹	Pooled: 38 studies, 3,098 patients (laser and LED)	Found: Hair density higher than placebo at under and over 20 weeks, with high heterogeneity (I² 81–88%)
Alahmadi 2026²²	Pooled: 37 studies, 3,298 patients (lasers and energy devices)	Found: Laser therapy added 18.56 hairs per cm² and 10.62 µm of shaft thickness over sham

What is still unknown

5 gaps

How long gains last, and what happens when you stop: the trials ran 4 to 26 weeks²¹, and reviewers ask for 12-month trials³⁰.
Which device works best: there is no head-to-head trial of caps, and none against finasteride or minoxidil²⁹.
Who it works for: the trials and the clearances cover skin types I–IV and early to moderate loss, and one large set of trials was 94.7% white^1,14.
The best wavelength, coherence and dose⁷, and whether near-infrared adds anything for hair²⁵.
How independent the evidence is: most trials were funded or run by the device makers^12,14,16.

With minoxidil or finasteride

Combination trials

With minoxidil: in a 45-woman trial without a sham, a laser helmet and minoxidil 5% gave comparable results, and the two together did best on Ludwig grade and satisfaction¹⁷. Two 2025 meta-analyses of the combination disagree, one finding 6.62 more hairs per cm² than minoxidil alone²⁶ and the other no difference²⁷.

With finasteride: we found no randomized trial of a laser cap together with finasteride in a PubMed search on Oct 18, 2026. Finasteride and minoxidil are approved drugs with larger, longer trials; see the men’s hair loss hub and the women’s hair loss hub.

How we sorted the devices

We sort the ten devices by five checks, in this order. A device only moves ahead on a later check when it ties on every earlier one. This is a sort order, not a score: there are no medals, and no device here has been tested by us.

Five checks, in order

Payment is not one of them

FDA clearance we could check. A 510(k) clearance that names the model, read on the FDA database; then a clearance the brand claims that we could not find; then devices the brand says are not cleared¹.
Light like the trials. Laser diodes at 650–655 nm, as in most trials^10,11,14, ahead of LED-only devices¹⁶.
A schedule the evidence tested. Sessions every other day or 3 to 4 times a week, as in the clearance and the main trials^2,14; less frequent sessions did better than more frequent ones in one meta-analysis¹⁹.
Time to judge it. A money-back window longer than 16 weeks, the shortest trial and the cleared first course².
Price. Lower first. Ties go to fewer wavelengths outside the red and near-infrared bands. We show price per diode or LED as a cost figure only: diode count did not predict results²⁴.

Commission All three brands on this list pay us a commission on a sale, at different rates. Commission never changes the order, the verdicts or what we leave in.

What the FDA database shows

Checked Oct 18, 2026

A 510(k) clearance means the FDA found a device substantially equivalent to one already on the market; it is not an approval⁵. Kiierr’s 2018 clearance, K181878, covers the 272 and 148 caps for pattern hair loss in men (Norwood-Hamilton IIa–V) and women (Ludwig-Savin I–II) with skin types I–IV, under product code OAP^1,2. Its summary says no clinical performance data were produced, because the caps are the same private-label device as an earlier cap, K173678, made by Cosmo Far East Technology^2,4.

Kiierr’s cap pages say “FDA Cleared”^37,38,39. The only 510(k) in Kiierr’s name is K181878¹. A 2025 clearance held by Cosmo Far East, K252325, lists 650 nm-only caps with 152 to 312 diodes, including 302- and 312-diode models, but it does not name Kiierr and lists no 808 nm diodes³. So for the 302, the DualWave caps and the Elite, Kiierr’s claim is one we could not verify.

Happy Head calls its helmet FDA-cleared without giving a number, and we found no 510(k) in its name^43,52. Hooga says its helmet and hats are wellness devices that are not FDA-cleared^40,41.

Every partner device, reviewed

Ten caps, helmets and hats from the three partners that sell them, in rubric order. Specs, prices and terms are each brand's own, read on Oct 18, 2026; we have not tested them.

The three brands

Terms that apply to every device they sell

KiierrSix laser caps
Kiierr, based in Salt Lake City², sells laser caps, LED combs, red light panels and skin devices^34,45,49. Every cap carries a 2-year warranty and a 7-month growth guarantee: register a before photo within 45 days, use the cap for 210 days, and return it between days 210 and 240 for a refund less a 25% fee, which is waived if you document the 7 months with photos³⁴.
Happy HeadOne laser helmet
Happy Head is an online hair-loss clinic; besides its prescription treatments it sells a laser helmet⁴³. Its program does not allow links to a product page, so our link opens Happy Head’s home page.
Hooga HealthOne laser helmet, two LED hats
Hooga sells red light panels, masks and other devices, and three for the scalp. It says plainly that its laser helmet and red light hat are not FDA-cleared for hair loss, and it claims no clearance for the ColorWave^40,41,42. Returns are accepted for 60 days from delivery, with return shipping deducted⁴¹.
12% off, applied automatically through our link. Shop through one of our Hooga links; Hooga applies 12% at checkout automatically. There is no code to type.

Kiierr 148 Pro
Paid links · we earn a commission
11 of 10 on our rubric · Laser cap
$799Oct 18, 2026
FDA 510(k) checked: K181878Laser diodes
Kiierr’s entry cap: 148 laser diodes at 650 nm, 740 mW in total by Kiierr’s figure, in a helmet that sits under a supplied baseball cap and runs off a battery pack. Kiierr’s directions are 30 minutes every other day³⁴, the regimen in the clearance that names this model².
Light
148 laser diodes; 650 nm
Sessions
30 min every other day
FDA
510(k) K181878, Sept 5, 2018^1,2
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$5.40 per diode
For
Its 510(k), K181878, names this model¹
650 nm laser diodes on an every-other-day schedule: the set-up closest to the sham-controlled trials^2,11,14
The 7-month refund window outlasts the 16 to 26 weeks the trials ran³⁴
Against
Cleared on equivalence, not new trials: the summary says no clinical data were produced²
The refund needs a before photo registered within 45 days, and a 25% fee unless you document 7 months of use³⁴
Our verdict: The cap closest to the evidence, for the least money among the cleared models.
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Kiierr 272 Premier
Paid links · we earn a commission
22 of 10 on our rubric · Laser cap
$1,199Oct 18, 2026
FDA 510(k) checked: K181878Laser diodes
The same cleared design as the 148 Pro with 272 laser diodes, 1,360 mW by Kiierr’s figure, and the same 30 minutes every other day. Kiierr says it is built to sit higher on the scalp, over the areas that most often thin³⁵.
Light
272 laser diodes; 650 nm
Sessions
30 min every other day
FDA
510(k) K181878, Sept 5, 2018^1,2
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$4.41 per diode
For
Its 510(k), K181878, names this model¹
Same trial-like light and schedule as the 148 Pro^2,35
Same 7-month refund window³⁵
Against
$400 more than the 148 Pro for more diodes, when diode count did not predict hair gains across the trials²⁴
Same refund conditions and 25% fee³⁵
Our verdict: Worth the extra only if you want more of the scalp under light at once; the evidence does not show more diodes grow more hair.
Shop at Kiierr (paid link, opens in new tab)
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Kiierr 272 Elite (XL)
Paid links · we earn a commission
33 of 10 on our rubric · Laser cap, larger size
$1,599Oct 18, 2026
Clearance not verifiedLaser diodes
A larger shell for heads up to 24.5 inches, with the 272 Premier’s 272 laser diodes at 650 nm and 1,360 mW, used 30 minutes every other day³⁶. Kiierr’s page says the technology is FDA cleared; the clearance we found names the 272 Premier and 148 Pro, not the Elite^1,36.
Light
272 laser diodes; 650 nm
Sessions
30 min every other day
FDA
Cleared per Kiierr; not in K181878’s device names^36,1
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$5.88 per diode
For
The only Kiierr cap sized for heads over 23.5 inches³⁶
Trial-like light and schedule³⁶
2-year warranty and the 7-month refund window³⁶
Against
$400 more than the 272 Premier^35,36
We could not match this model to a 510(k)¹
Our verdict: Buy it only if the standard cap does not fit.
Shop at Kiierr (paid link, opens in new tab)
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Happy Head Laser Helmet
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44 of 10 on our rubric · Laser helmet
$998Oct 18, 2026
Clearance not verifiedLaser diodes
A helmet with 204 laser diodes at 650 nm from the online clinic Happy Head, used for 25 to 35 minutes 3 to 4 times a week by its page⁴³. The page calls it FDA-cleared but gives no clearance number, and we found none in Happy Head’s name^43,52.
Light
204 laser diodes; 650 nm
Sessions
25–35 min, 3 to 4 times a week
FDA
Cleared per Happy Head; no 510(k) number given or found^43,52
Warranty
Not stated on its page
Money back
Returns within 30 days of delivery, at your shipping cost; the 6-month guarantee excludes non-prescription products
Cost per emitter
$4.89 per diode
For
650 nm laser diodes⁴³
A schedule close to the laser-comb trials, which used 3 sessions a week^14,43
Against
No clearance number to check^43,52
Returns only within 30 days of delivery, long before results could show; the refund is at Happy Head’s discretion⁴⁴
Our link opens Happy Head’s home page, not the helmet page
Our verdict: Specs in line with the laser trials, but you cannot check the clearance and the return window is the shortest here.
Start a Happy Head consultation (paid link, opens in new tab)
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Kiierr 272 DualWave
Paid links · we earn a commission
55 of 10 on our rubric · Flexible laser cap
$1,499Oct 18, 2026
Clearance not verifiedLaser diodes
A lighter, flexible cap that adds near-infrared lasers, used 6 minutes a day³⁸. Its spec line lists 232 lasers at 650 nm and 20 at 808 nm, which adds up to 252, not the 272 in its name³⁸.
Light
272 laser diodes by name; the spec line adds to 252; 650 + 808 nm
Sessions
6 min daily
FDA
Cleared per Kiierr; no 510(k) found for this model^38,1,3
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$5.51 per diode
For
Six-minute daily sessions³⁸
650 nm laser diodes, plus near-infrared³⁸
7-month refund window³⁸
Against
Near-infrared for pattern hair loss rests on fewer studies²⁵
A daily schedule unlike the cleared every-other-day regimen^2,38
No 510(k) we could find, and a spec sheet that does not add up^1,38
Our verdict: Hard to choose over the 272 Premier, which costs $300 less and has a clearance you can check.
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Kiierr 302 Ultra Flex
Paid links · we earn a commission
66 of 10 on our rubric · Flexible laser cap
$1,799Oct 18, 2026
Clearance not verifiedLaser diodes
302 laser diodes at 650 nm, 1,510 mW by Kiierr’s figure, in a lighter, flexible cap used 6 minutes a day³⁷. The 2025 OEM clearance K252325 lists a 302-diode, 650 nm cap, but it does not name Kiierr³.
Light
302 laser diodes; 650 nm
Sessions
6 min daily
FDA
Cleared per Kiierr; a 302-diode OEM model is cleared without Kiierr’s name^37,1,3
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$5.96 per diode
For
Six-minute daily sessions³⁷
650 nm laser diodes³⁷
7-month refund window³⁷
Against
Daily sessions, unlike the cleared every-other-day regimen; less frequent sessions did better in one meta-analysis^2,19
$1,799, and no clearance in Kiierr’s name¹
Our verdict: Shorter sessions, but further from the evidence than the 148 Pro or 272 Premier.
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Kiierr 312 DualWave
Paid links · we earn a commission
77 of 10 on our rubric · Flexible laser cap
$2,199Oct 18, 2026
Clearance not verifiedLaser diodes
Kiierr’s top cap: 272 lasers at 650 nm and 40 near-infrared lasers at 808 nm, 1,560 mW by Kiierr’s figure, used 6 minutes a day³⁹. The OEM clearance K252325 lists a 312-diode cap at 650 nm only³.
Light
312 laser diodes (272 at 650 nm, 40 at 808 nm); 650 + 808 nm
Sessions
6 min daily
FDA
Cleared per Kiierr; no 510(k) found for this model^39,1,3
Warranty
2 years
Money back
7-month growth guarantee (25% fee unless photos are documented)
Cost per emitter
$7.05 per diode
For
The most diodes of any device here³⁹
Six-minute daily sessions³⁹
7-month refund window³⁹
Against
The most expensive device here³⁹
Near-infrared for hair rests on fewer studies²⁵
No 510(k) we could find for a cap with 808 nm diodes^1,3
Our verdict: The most diodes and the highest price, for benefits the trials have not shown.
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Hooga Red Light Therapy Laser Helmet
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88 of 10 on our rubric · Laser helmet
$499Oct 18, 2026
Not FDA-clearedLaser diodes
A cordless helmet with 96 laser diodes at 650 ± 5 nm, 5 mW each by Hooga’s figures, run in 10-minute sessions with a sensor that pauses the light when the helmet moves⁴⁰. Hooga calls it a wellness device and says it is not FDA-cleared for hair loss⁴⁰.
Light
96 laser diodes, 5 mW each; 650 ± 5 nm
Sessions
10 min daily
FDA
Not FDA-cleared, Hooga says⁴⁰
Warranty
2 years
Money back
60-day returns from delivery; return shipping deducted
Cost per emitter
$5.20 per diode
For
The cheapest laser device here, before the 12% our link applies⁴⁰
650 nm laser diodes, the wavelength most trials used^10,14,40
2-year warranty⁴⁰
Against
Not FDA-cleared, by Hooga’s own statement⁴⁰
The 60-day return window ends before the shortest trial did^11,41
Our verdict: The low-cost way to try a laser device, from a brand that says plainly it is not cleared.
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Hooga Red Light Therapy Hat
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99 of 10 on our rubric · LED hat
$299Oct 18, 2026
Not FDA-clearedLEDs
A light, plug-in hat with 150 LEDs that each give red (660 nm) and near-infrared (850 nm) light, and a built-in timer⁴¹. Hooga lists 100 mW/cm² at the surface, its own figure. Its copy describes 10-minute sessions, while its spec list says “Timer: 15 Minute Automatic”⁴¹.
Light
150 dual-chip LEDs; 660 + 850 nm
Sessions
10-min timer in the copy; the spec list says 15
FDA
Not FDA-cleared, Hooga says⁴¹
Warranty
1 year
Money back
60-day returns from delivery; return shipping deducted
Cost per emitter
$1.99 per LED
For
$299, before the 12% our link applies⁴¹
Red and near-infrared in every LED⁴¹
Weighs a quarter of a pound⁴¹
Against
LEDs only: the one sham-controlled LED cap trial was mixed¹⁶
Not FDA-cleared⁴¹; 1-year warranty; corded⁴¹
Our verdict: If you choose an LED hat, this is the plainer of Hooga’s two; expect less certainty than with a laser cap.
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Hooga ColorWave Light Therapy Hat
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1010 of 10 on our rubric · LED hat
$299Oct 18, 2026
Not FDA-clearedLEDs
The same 150-LED hat with quad-chip LEDs that add green (520 nm) and blue (415 nm) to red and near-infrared, a 10 Hz pulse option and a 10 or 15-minute timer⁴².
Light
150 quad-chip LEDs; 660 + 850 nm, plus 520 and 415 nm
Sessions
10 or 15 min; optional 10 Hz pulse
FDA
No clearance claimed⁴²
Warranty
1 year
Money back
60-day returns from delivery; return shipping deducted
Cost per emitter
$1.99 per LED
For
Same price as the plain hat^41,42
A pulse option: pulsed light went with larger gains across the laser trials, though no trial tested this hat²⁴
Against
In the one LED cap trial with a blue-light arm, no single arm beat sham¹⁶
Not FDA-cleared; 1-year warranty⁴²
Our verdict: Pick it over the plain hat only for the pulse option; the extra colours add nothing the hair trials have shown.
Shop at Hooga (paid link, opens in new tab)
Partner links may earn us a commission. How partner links work

What our due diligence found on Hooga Health

Hooga is a founder-owned company in New Berlin, Wisconsin, founded in 2018. Its panels are built by an overseas contract manufacturer whose facility Hooga says is ISO 13485 certified. Source: Hooga: About (read Oct 16, 2026)
Hooga says its HG, PRO and ULTRA panels are listed with the FDA as Class II devices under product code ILY, a 510(k)-exempt type, so they have no 510(k) clearance, and that the finished panels carry no UL or ETL safety listing. Source: Hooga: Quality & Certifications (read Oct 16, 2026)
Hooga’s irradiance, EMF and flicker figures are its own. An independent reviewer Hooga cites measured its ULTRA1500 at 104 mW/cm² peak and 81.7 mW/cm² average at 6 inches, below Hooga’s published figure. Source: Hooga: Quality & Certifications (read Oct 16, 2026)
Hooga lists its Luma mask under 510(k) K253712. The FDA record is held by Shenzhen Rainbow Technology Co., Ltd. for an LED Light Therapy Mask, models RB-051 to RB-073, and does not name Luma or Hooga. Source: FDA 510(k) database: K253712 (read Oct 16, 2026)

Also sold, not reviewed

Not partners: not linked, not ranked

BON CHARGE Red Light Cap: BON CHARGE sells a Red Light Cap with 650 nm LEDs, used 10 minutes a day, listed at $449 on Oct 18, 2026. Its page says “FDA Cleared” without a 510(k) number, and we found no clearance in its name^51,52. BON CHARGE does not pay us, so it is named here for completeness and not linked or ranked.
HairMax LaserComb: The device behind the largest laser trials^10,14, cleared by the FDA in January 2007 (K060305)³³. Its maker is not a partner of ours.

Side by side

All ten devices in rubric order. Prices as listed on Oct 18, 2026, before tax, shipping and any discount.

Ten red light hair devices compared

Brands' own specs, Oct 18, 2026

Ten laser caps, helmets and LED hats compared by type, light, sessions, FDA status, price, warranty and our verdict, in rubric order.
10 devices	148 ProRead the review	272 PremierRead the review	272 Elite XLRead the review	Happy Head helmetRead the review	272 DualWaveRead the review	302 Ultra FlexRead the review	312 DualWaveRead the review	Hooga laser helmetRead the review	Hooga hatRead the review	Hooga ColorWaveRead the review
Type	Laser cap (laser)	Laser cap (laser)	Laser cap, larger size (laser)	Laser helmet (laser)	Flexible laser cap (laser)	Flexible laser cap (laser)	Flexible laser cap (laser)	Laser helmet (laser)	LED hat (LED)	LED hat (LED)
Diodes or LEDs	148 laser diodes	272 laser diodes	272 laser diodes	204 laser diodes	272 laser diodes by name; the spec line adds to 252	302 laser diodes	312 laser diodes (272 at 650 nm, 40 at 808 nm)	96 laser diodes, 5 mW each	150 dual-chip LEDs	150 quad-chip LEDs
Wavelength	650 nm	650 nm	650 nm	650 nm	650 + 808 nm	650 nm	650 + 808 nm	650 ± 5 nm	660 + 850 nm	660 + 850 nm, plus 520 and 415 nm
Sessions	30 min every other day	30 min every other day	30 min every other day	25–35 min, 3 to 4 times a week	6 min daily	6 min daily	6 min daily	10 min daily	10-min timer in the copy; the spec list says 15	10 or 15 min; optional 10 Hz pulse
FDA 510(k)	K181878	K181878	Not verified	Not verified	Not verified	Not verified	Not verified	Not cleared	Not cleared	Not cleared
PriceOct 18, 2026	$799	$1,199	$1,599	$998	$1,499	$1,799	$2,199	$499	$299	$299
Per diode or LEDCost only	$5.40	$4.41	$5.88	$4.89	$5.51	$5.96	$7.05	$5.20	$1.99	$1.99
Warranty and money back	2 years. 7-month growth guarantee (25% fee unless photos are documented)	2 years. 7-month growth guarantee (25% fee unless photos are documented)	2 years. 7-month growth guarantee (25% fee unless photos are documented)	Not stated on its page. Returns within 30 days of delivery, at your shipping cost; the 6-month guarantee excludes non-prescription products	2 years. 7-month growth guarantee (25% fee unless photos are documented)	2 years. 7-month growth guarantee (25% fee unless photos are documented)	2 years. 7-month growth guarantee (25% fee unless photos are documented)	2 years. 60-day returns from delivery; return shipping deducted	1 year. 60-day returns from delivery; return shipping deducted	1 year. 60-day returns from delivery; return shipping deducted
Our verdict	The cap closest to the evidence, for the least money among the cleared models.	Worth the extra only if you want more of the scalp under light at once; the evidence does not show more diodes grow more hair.	Buy it only if the standard cap does not fit.	Specs in line with the laser trials, but you cannot check the clearance and the return window is the shortest here.	Hard to choose over the 272 Premier, which costs $300 less and has a clearance you can check.	Shorter sessions, but further from the evidence than the 148 Pro or 272 Premier.	The most diodes and the highest price, for benefits the trials have not shown.	The low-cost way to try a laser device, from a brand that says plainly it is not cleared.	If you choose an LED hat, this is the plainer of Hooga’s two; expect less certainty than with a laser cap.	Pick it over the plain hat only for the pulse option; the extra colours add nothing the hair trials have shown.

Kiierr 148 ProRead the review
Price
$799
$5.40 per diode
Type
Laser cap (laser)
Diodes or LEDs
148 laser diodes
Wavelength
650 nm
Sessions
30 min every other day
FDA 510(k)
K181878
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
The cap closest to the evidence, for the least money among the cleared models.
Kiierr 272 PremierRead the review
Price
$1,199
$4.41 per diode
Type
Laser cap (laser)
Diodes or LEDs
272 laser diodes
Wavelength
650 nm
Sessions
30 min every other day
FDA 510(k)
K181878
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
Worth the extra only if you want more of the scalp under light at once; the evidence does not show more diodes grow more hair.
Kiierr 272 Elite (XL)Read the review
Price
$1,599
$5.88 per diode
Type
Laser cap, larger size (laser)
Diodes or LEDs
272 laser diodes
Wavelength
650 nm
Sessions
30 min every other day
FDA 510(k)
Not verified
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
Buy it only if the standard cap does not fit.
Happy Head Laser HelmetRead the review
Price
$998
$4.89 per diode
Type
Laser helmet (laser)
Diodes or LEDs
204 laser diodes
Wavelength
650 nm
Sessions
25–35 min, 3 to 4 times a week
FDA 510(k)
Not verified
Warranty and money back
Not stated on its page. Returns within 30 days of delivery, at your shipping cost; the 6-month guarantee excludes non-prescription products
Our verdict
Specs in line with the laser trials, but you cannot check the clearance and the return window is the shortest here.
Kiierr 272 DualWaveRead the review
Price
$1,499
$5.51 per diode
Type
Flexible laser cap (laser)
Diodes or LEDs
272 laser diodes by name; the spec line adds to 252
Wavelength
650 + 808 nm
Sessions
6 min daily
FDA 510(k)
Not verified
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
Hard to choose over the 272 Premier, which costs $300 less and has a clearance you can check.
Kiierr 302 Ultra FlexRead the review
Price
$1,799
$5.96 per diode
Type
Flexible laser cap (laser)
Diodes or LEDs
302 laser diodes
Wavelength
650 nm
Sessions
6 min daily
FDA 510(k)
Not verified
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
Shorter sessions, but further from the evidence than the 148 Pro or 272 Premier.
Kiierr 312 DualWaveRead the review
Price
$2,199
$7.05 per diode
Type
Flexible laser cap (laser)
Diodes or LEDs
312 laser diodes (272 at 650 nm, 40 at 808 nm)
Wavelength
650 + 808 nm
Sessions
6 min daily
FDA 510(k)
Not verified
Warranty and money back
2 years. 7-month growth guarantee (25% fee unless photos are documented)
Our verdict
The most diodes and the highest price, for benefits the trials have not shown.
Hooga Red Light Therapy Laser HelmetRead the review
Price
$499
$5.20 per diode
Type
Laser helmet (laser)
Diodes or LEDs
96 laser diodes, 5 mW each
Wavelength
650 ± 5 nm
Sessions
10 min daily
FDA 510(k)
Not cleared
Warranty and money back
2 years. 60-day returns from delivery; return shipping deducted
Our verdict
The low-cost way to try a laser device, from a brand that says plainly it is not cleared.
Hooga Red Light Therapy HatRead the review
Price
$299
$1.99 per LED
Type
LED hat (LED)
Diodes or LEDs
150 dual-chip LEDs
Wavelength
660 + 850 nm
Sessions
10-min timer in the copy; the spec list says 15
FDA 510(k)
Not cleared
Warranty and money back
1 year. 60-day returns from delivery; return shipping deducted
Our verdict
If you choose an LED hat, this is the plainer of Hooga’s two; expect less certainty than with a laser cap.
Hooga ColorWave Light Therapy HatRead the review
Price
$299
$1.99 per LED
Type
LED hat (LED)
Diodes or LEDs
150 quad-chip LEDs
Wavelength
660 + 850 nm, plus 520 and 415 nm
Sessions
10 or 15 min; optional 10 Hz pulse
FDA 510(k)
Not cleared
Warranty and money back
1 year. 60-day returns from delivery; return shipping deducted
Our verdict
Pick it over the plain hat only for the pulse option; the extra colours add nothing the hair trials have shown.

Other red light devices from our partners

Masks, combs, wands and panels from the same brands. They are not hair caps, so we do not review or rank them here.

Beyond the hair caps

Brands' own specs, Oct 18, 2026 Paid links · we earn a commission

Other red light devices sold by our partners
Device	What it is	Price (Oct 18, 2026)
Kiierr Hair Growth Comb (paid link, opens in new tab)⁴⁵	What it is: LED comb with vibration: 84 LEDs, 630 nm red and 450 nm blue; 5–10 min, 3–5 times a week; 90-day money-back	$239
Kiierr Restore comb (paid link, opens in new tab)⁴⁶	What it is: Massage comb with 25 LEDs (630 nm red, 450 nm blue) and microcurrent; Kiierr calls it an add-on, not a replacement for a cap	$179.99
Kiierr Revive mask (paid link, opens in new tab)⁴⁷	What it is: Face mask with 216 LEDs at 850, 630, 590 and 415 nm; 10–30 min sessions	$399
Kiierr Miracle Wand (paid link, opens in new tab)⁴⁸	What it is: Handheld face wand: 630 nm red light with microcurrent, warmth and vibration; 5-minute timer	$99
Kiierr RH red light panels (paid link, opens in new tab)^49,50	What it is: LED panels with 630 and 660 nm red and 810, 830 and 850 nm near-infrared (the RH300 has 70 LEDs); 5–30 min at 6–12 in; 6-month money-back	RH300 $399 to RH3600 $2,399
Hooga panels, masks, belt and blanket	What it is: Red and near-infrared LED panels, the Luma face mask, a belt and a full-body blanket, compared with Hooga’s own specs in our red light therapy guide	See the guide

Safety, and who should not use one

In the trials, side effects were few: none in the helmet trials^11,12, no serious ones with the laser comb¹⁴, and temporary shedding and scalp itch in one helmet trial¹⁵. A review notes shedding that started 1 to 2 months into laser-comb use and stopped with continued use⁷. Reviewers describe the safety record as excellent, while saying long-term studies are missing²⁹.

The clearances cover pattern hair loss only¹. Hair that falls out suddenly, in patches or with scalp pain needs a diagnosis first; see how long stress shedding lasts.

Eyes: the cleared caps use class 3R laser diodes². Never look into the diodes⁴⁰. Laser red-light devices aimed at the eye for myopia reached eye-safety limits within seconds in lab tests²⁸.
Light sensitivity: the largest trials excluded people with a history of photosensitivity to laser light¹⁴. If you take a medicine that makes skin sensitive to light or have a light-sensitive condition, ask your clinician first, as Hooga’s own pages advise⁴².
A spot on the scalp that is new or changing: get it checked first. A review raises the possibility that the light could stimulate abnormal or cancerous scalp lesions⁷, and the trials excluded anyone with cancer in the treated area in the past 5 years¹⁴.
Pregnancy: the trials excluded women who were or planned to become pregnant¹⁴, so there are no data.
Pacemakers and other implanted devices: the laser-comb trials excluded them¹⁴. Ask the device maker or your cardiologist.
Pulsed modes: if flashing light can trigger a seizure or migraine for you, leave the ColorWave’s 10 Hz pulse off⁴².
Skin types V–VI and advanced baldness fall outside what the clearances and most trials cover^1,14.

Quick answers

Questions about laser caps and red light hats

9 answers

Do red light hats actually regrow hair?

For pattern hair loss, laser devices raised hair counts more than sham devices in randomized trials, by about 18.6 hairs per cm² on average²². The effect is modest, most people in the trials had early to moderate loss, and the trials lasted 16 to 26 weeks^14,29. LED-only hats have less evidence: one trial, with a mixed result¹⁶.

Is a laser cap better than an LED hat?

No trial compares them head to head²⁹. Most of the hair evidence comes from lasers, alone or with LEDs^10,11,14, and devices with laser diodes alone showed a larger pooled effect²⁰. The one LED-only cap trial found no single cap beat sham¹⁶.

What wavelength should a hair cap use?

Most trials used red light near 655 nm^10,11,14; one used 630 to 660 nm¹³. Near-infrared (around 808 to 850 nm) has fewer hair studies²⁵. Blue light alone did not beat sham in the one trial that tested it¹⁶; we found no hair trial of green light.

What does FDA-cleared mean for a laser cap?

Cleared through a 510(k): the FDA found the device substantially equivalent to one already sold. It is not FDA approval⁵. Kiierr’s clearance, K181878, says no clinical data were produced for it². You can look up any number on the FDA 510(k) database⁵².

How long until I see results?

The cleared course is 30 minutes every other day for an initial 16 weeks², and the trials measured results at 16 to 26 weeks^11,14. Some trials saw temporary shedding in the first 1 to 2 months^7,15.

Can I use a laser cap with minoxidil or finasteride?

Two 2025 meta-analyses of laser plus minoxidil disagree on whether it adds anything^26,27. We found no randomized trial of a cap with finasteride. Ask your clinician; caps are not a substitute for the approved drugs, which have larger, longer trials.

Do more diodes work better?

Not that the trials show. An analysis across the randomized trials found the number of diodes was not linked to hair gains, while energy per session and total time under the light were²⁴.

Who should not use a red light cap?

Talk to a clinician first if you are pregnant, are sensitive to light or take a photosensitizing medicine, have a changing spot on your scalp, or have a pacemaker or other implanted device; the trials excluded these groups¹⁴. Never look into the diodes⁴⁰.

Is there a Kiierr or Hooga discount?

When we last checked (Oct 16, 2026), arriving through our Hooga link applied a 12% referral discount at checkout, with no code to type. We have no Kiierr discount to offer.

Related pages and sources

Every study, FDA record and brand page we read for this review, numbered as in the text.

8 pages

Keep reading: Supplements and vitamins

Supplements and vitamins: every page Supplement & Nutrient Encyclopedia Browse all topics

Evidence-graded supplement stacks

Researched and written by Kymata Health Editorial; sources cited inline. Drawn from the studies and documents cited below. Educational only, not medical advice.

Sources

52 sources

1FDA 510(k) database: K181878, Kiierr 272 Laser, Kiierr 148 Laser. US FDA, 2018.
2K181878 decision letter, indications and 510(k) summary (Kiierr). US FDA, 2018.
3K252325 decision letter and 510(k) summary (Cosmo Far East). US FDA, 2025.
4FDA 510(k) database: K173678, Diode Laser Cap (Cosmo Far East). US FDA, 2018.
5Premarket Notification 510(k). US FDA, 2024.
6Proposed mechanisms of photobiomodulation or low-level light therapy. IEEE J Sel Top Quantum Electron, 2016. PMID 28070154
7Low-level laser (light) therapy (LLLT) for treatment of hair loss. Lasers Surg Med, 2014. PMID 23970445
8Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Semin Cutan Med Surg, 2013. PMID 24049929
9Photobiomodulation: lasers vs. light emitting diodes?. Photochem Photobiol Sci, 2018. PMID 30044464
10HairMax LaserComb laser phototherapy device in the treatment of male androgenetic alopecia: a randomized, double-blind, sham device-controlled, multicentre trial. Clin Drug Investig, 2009. PMID 19366270
11The growth of human scalp hair mediated by visible red light laser and LED sources in males. Lasers Surg Med, 2013. PMID 24078483
12The growth of human scalp hair in females using visible red light laser and LED sources. Lasers Surg Med, 2014. PMID 25124964
13Low-level light therapy for androgenetic alopecia: a 24-week, randomized, double-blind, sham device-controlled multicenter trial. Dermatol Surg, 2013. PMID 23551662
14Efficacy and safety of a low-level laser device in the treatment of male and female pattern hair loss: a multicenter, randomized, sham device-controlled, double-blind study. Am J Clin Dermatol, 2014. PMID 24474647
15Low-level laser therapy for the treatment of androgenetic alopecia in Thai men and women: a 24-week, randomized, double-blind, sham device-controlled trial. Lasers Med Sci, 2019. PMID 30569416
16Clinical safety and efficacy of dual wavelength low-level light therapy in androgenetic alopecia: a double-blind randomized controlled study. Dermatol Surg, 2025. PMID 39679573
17Low level light-minoxidil 5% combination versus either therapeutic modality alone in management of female patterned hair loss: a randomized controlled study. Lasers Surg Med, 2017. PMID 28489273
18The effectiveness of treatments for androgenetic alopecia: a systematic review and meta-analysis. J Am Acad Dermatol, 2017. PMID 28396101
19Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a system review and meta-analysis of randomized controlled trials. Lasers Med Sci, 2019. PMID 30706177
20A systematic review and meta-analysis of randomized controlled trials of United States Food and Drug Administration-approved, home-use, low-level light/laser therapy devices for pattern hair loss: device design and technology. J Clin Aesthet Dermatol, 2021. PMID 34980962
21Low-level laser and LED therapy in alopecia: a systematic review and meta-analysis. Dermatol Surg, 2025. PMID 39404126
22Lasers and energy-based devices in the treatment of androgenetic alopecia: a systematic review and meta-analysis. Skin Appendage Disord, 2026. PMID 42339398
23Interventions for female pattern hair loss. Cochrane Database Syst Rev, 2016. PMID 27225981
24Factors influencing the effect of photobiomodulation in the treatment of androgenetic alopecia: a systematic review and analyses of summary-level data. Dermatol Ther, 2020. PMID 32790116
25Photobiomodulation therapy with different wavebands for hair loss: a systematic review and meta-analysis. Dermatol Surg, 2022. PMID 35510860
26Comparative efficacy and safety of low-level laser therapy and topical minoxidil combination vs. topical minoxidil monotherapy in androgenetic alopecia management: a systematic review and meta-analysis of randomized controlled trials. Lasers Med Sci, 2025. PMID 40826200
27Comparative efficacy of minoxidil alone versus minoxidil combined with low-level laser therapy in the treatment of androgenic alopecia: a systematic review and meta-analysis. J Dermatolog Treat, 2025. PMID 39828269
28Safety evaluation of 4 red light therapy devices for myopia. JAMA Ophthalmol, 2026. PMID 41642586
29Photobiomodulation therapy for androgenetic alopecia: a clinician’s guide to home-use devices cleared by the Federal Drug Administration. J Cosmet Laser Ther, 2018. PMID 29020478
30A critical assessment of the evidence for low-level laser therapy in the treatment of hair loss. Dermatol Surg, 2017. PMID 27618394
31Efficacy of non-surgical treatments for androgenetic alopecia: a systematic review and network meta-analysis. J Eur Acad Dermatol Venereol, 2018. PMID 29797431
32Photobiomodulation for the management of hair loss. Photodermatol Photoimmunol Photomed, 2021. PMID 33377535
33FDA 510(k) database: K060305, HairMax LaserComb. US FDA, 2007.
34Kiierr 148 Pro: specs, directions, warranty and 7-month growth guarantee, price. Kiierr, 2026.
35Kiierr 272 Premier: specs, sizing, warranty and guarantee, price. Kiierr, 2026.
36Kiierr 272 Elite (XL): specs, sizing, FDA statement, bundle, price. Kiierr, 2026.
37Kiierr 302 Ultra Flex: specs, directions, warranty and guarantee, price. Kiierr, 2026.
38Kiierr 272 DualWave: specs (diode counts by wavelength), directions, price. Kiierr, 2026.
39Kiierr 312 DualWave: specs (diode counts by wavelength), directions, price. Kiierr, 2026.
40Hooga Red Light Therapy Laser Helmet: specs, FDA statement, safety, warranty, price. Hooga, 2026.
41Hooga Red Light Therapy Hat: specs, FDA statement, warranty and returns, price. Hooga, 2026.
42Hooga ColorWave Light Therapy Hat: specs, modes, safety notice, price. Hooga, 2026.
43Happy Head Laser Helmet: specs, directions, FDA statement, price. Happy Head, 2026.
44Happy Head terms of use: refund and return policy, money-back guarantee. Happy Head, 2026.
45Kiierr Hair Growth Comb: LEDs, wavelengths, directions, guarantee, price. Kiierr, 2026.
46Kiierr Restore 4-in-1 comb: LEDs, wavelengths, directions, price. Kiierr, 2026.
47Kiierr Revive mask: LEDs, wavelengths, session length, price. Kiierr, 2026.
48Kiierr Miracle Wand: wavelength, timer, guarantee, price. Kiierr, 2026.
49Kiierr RH300 red light panel: LEDs, wavelengths, directions, guarantee, price. Kiierr, 2026.
50Kiierr RH3600 red light panel: price. Kiierr, 2026.
51BON CHARGE Red Light Cap: specs, directions, warranty, price. BON CHARGE, 2026.
52FDA 510(k) database, searched by applicant and device name. US FDA, 2026.

Laser caps and red light hats are sold for pattern hair loss or for general wellness. Nothing here is medical advice or a claim that a device diagnoses, cures or prevents any condition. Talk to your clinician before using light therapy if you have a medical condition, take photosensitizing medicines, or are pregnant or breastfeeding.