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Track orders, troubleshoot your device, browse 50+ FAQs, or schedule a free consultation with a hair growth expert.

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Urgent Order Change

Orders ship fast — act immediately before fulfillment begins.

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Return / Growth Guarantee

Eligible after 7 months of consistent use. Email refunds@kiierr.com.

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Device Troubleshooting

Use the below troubleshooting guide to resolve your laser cap issue.

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Battery / Part Replacement

Order a replacement battery, charging cord, or other accessory.

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Warranty Claim

File a claim for an issue with your Kiierr device or delivery.

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Monthly Progress Photo

You can submit monthly or at the end of 7 months.

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Register My Device

Must register within 45 days of receiving your cap to qualify.

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Subscription / Auto-Ship

Manage, pause, or cancel your supplement auto-ship subscription.

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Order Tracking

Track your Kiierr order

Once your order ships you'll receive a confirmation email with a tracking link. You can also track through the Shop app or by logging into your account. Processing time for most orders is 3-5 business days. If you do not see the tracking number in your account, please email service@kiierr.com

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NEW CUSTOMERS

Not sure where to begin?

Whether you're researching laser therapy for the first time or ready to choose a model, our hair growth experts are here to help. Browse quick-start topics below or book a free one-on-one consultation.

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Is Kiierr right for me?

Who benefits, hair types, skin tones, age, and medical considerations.

Browse FAQs

Which model should I choose?

Compare all models: 148 Pro, 272 Premier, DualWave, 302 UltraFlex, and 312.

Compare models

Growth guarantee & returns

Our 7-month money-back guarantee, registration, and refund policy.

Learn more

Payment & financing

Accepted payment methods, FSA/HSA, and financing options.

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Book a free consultation

Speak 1-on-1 with a hair growth expert to find the right solution.

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Talk to a hair growth expert — free

Our specialists can help you choose the right cap, understand the treatment process, and answer any questions before you buy.

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Laser Cap Troubleshooting

Mirrored Battery

Mirror battery with four indicator lights on top and a power button. Twist-lock connector between cap cable and battery.

Battery A

Gray Battery

Gray rectangular battery pack with a flip switch on the top. Connects to cap via USB cord with a twist-lock connector.

Battery C

New Black Battery

Soft flexible cap design. Battery has four indicator lights. Cable connects via white arrow alignment. 6- minute daily sessions.

Battery D

Select your battery above to see troubleshooting steps specific to your device.

Mirrored Battery

Mirror battery with four indicator lights on top and a power button. Twist-lock connector between cap cable and battery.

Battery is on but lasers are not turning on

Battery shuts off shortly after turning on

Battery is beeping during a session

Cap only works when the cord is at a specific angle

Can I plug the cap directly into the wall while waiting for a replacement?

Cap is sitting high on my head

Is it normal for the lasers to flash (pulse) during my session?

Gray Battery

Gray rectangular battery pack with a flip switch on the top. Connects to cap via USB cord with a twist-lock connector.

Battery indicator light behavior explained

Battery is on but lasers are not turning on

Battery keeps beeping but lasers won't activate

Battery shuts off shortly after turning on

Cap only works when the cord is held at a specific angle

Can I plug the cap directly into the wall while waiting for a replacement battery?

New Black Battery

Soft flexible cap design. Battery has four indicator lights. Cable connects via white arrow alignment and twist-lock. Sessions are 6 minutes daily. Device beeps once at startand three times at end of each session.

How to charge Battery D correctly

1

Plug the AC adapter into the battery and into a wall outlet. While charging, the indicator lights on top of the battery should flash — this confirms charging is in progress.

2

Plug the charging cord into the battery and into a wall outlet. A red light should appear on the wall charger, confirming charging is in progress.

3

If no lights appear at all, unplug both ends completely, reconnect securely, and try a different wall outlet.

4

A full charge is complete when all four indicator lights stay on solid without blinking.

5

Disconnect the AC adapter completely from the battery before use. The battery will not power the cap while the adapter is still connected.

Only use the original Kiierr charging adapter. Third-party chargers are not compatible and may damage the battery or prevent charging.

What the indicator lights mean during charging

Battery is on but lasers are not turning on

Cap is not responding at all when powered on

Treatment stops unexpectedly mid-session

How to use the cap — step by step

Cap fit and coverage

Will the cap treat areas it's not directly covering?

Can I use the cap more than once a day?

Can I use the cap on wet hair?

How do I clean my cap?

Frequently Asked Questions

Browse by category

Showing all 51 questions

Will Kiierr work for me?

New customers

Kiierr is designed for adults 18+ of all genders, ages, ethnicities, hair colors, and hair types—including straight, wavy, curly, and coily hair. We’ve even had customers in their 70s and 80s report positive results.


It can help with male and female pattern hair loss, hereditary thinning, receding hairlines, thinning crowns, widening parts, diffuse thinning, and age-related hair loss. Hair loss does not have to be mild, people with more advanced thinning may still benefit as long as active follicles remain.

Is Kiierr FDA-cleared? Is it safe?

New customers

Yes, Kiierr laser caps are FDA-cleared Class II medical devices that use Class 3R low-level laser therapy (LLLT)and are manufactured under ISO 13485 medical device quality standards.


LLLT is non-invasive, drug-free, and non-heating and has been used in hair restoration for decades. Clinical research supports its safety and effectiveness for hair growth, with a low risk of significant side effects when used as directed.

Why choose Kiierr over minoxidil, finasteride, or other hair loss treatments?

New customers

Minoxidil and finasteride can be effective, but many people choose Kiierr because it is drug-free, non-invasive, and does not alter your hormones. There are no pills to take or topical solutions to apply, and you avoid the potential drug-related side effects associated with these treatments.


Kiierr uses low-level laser therapy (LLLT) to stimulate your own hair follicles and support healthier growth. Clinical research supports LLLT as an effective treatment for pattern hair loss. It can also be used alongside minoxidil, finasteride, or other treatments for customers who want a combined approach.

I'm completely bald — will it work for me?

New customers

LLLT stimulates existing hair follicles — it cannot create new follicles where none remain. If an area of the scalp is completely bald and follicles are no longer active, laser therapy will not produce results in that area. Kiierr is most effective in early to advanced stages of hair loss while some follicles are still present and viable.

Does Kiierr work for both men and women?

New customers

Yes. All Kiierr laser caps are designed for both men and women. The laser technology itself does not change based on gender, so there is no need to choose a separate “men’s” or “women’s” cap.


The same cap can be used to help with common forms of thinning in both men and women, including receding hairlines, crown thinning, widening parts, and overall loss of density. Your choice should be based on the model, fit, diode count, and features you want—not gender.

Can I use Kiierr if I'm pregnant or nursing?

New customers

Please consult your physician for individual guidance before using any LLLT device during pregnancy or while breastfeeding.

Can people with darker skin tones use Kiierr?

New customers

Kiierr is FDA cleared for people with light-medium skin types. However, that’s only because there weren’t enough test subjects with darker skin types. Due to this, we must specify that it is not FDA cleared for those with darker complextions. With that being said, we have had many people of color use our product and achieve fantastic results, sometimes even better than those with fair complexions. All of our customers, regardless of skin tone, are eligible for our growth guarantee. Please let us know if you have any questions.

Is there a money-back guarantee?

New customers

Yes — Kiierr offers a 7-month growth guarantee. If you use your cap consistently as directed and do not see hair growth after 7 months, you can request a refund. To qualify, your cap must be registered within 45 days of receipt with a before photo, and your return request must be submitted between days 210–240. A 25% service fee applies, which is waived if you submit 7 monthly progress photos with date stamps.

What model should I choose?

Models & specs

The 148 Pro is our best entry-level option for those with very early-stage thinning, mild hair loss, or those looking to be proactive about maintaining their hair. It offers effective laser coverage at a more accessible price point and is used for 30 minutes every other day.


The 272 Premier is ideal for those with moderate thinning who want more laser coverage and power than the 148 Pro. It provides broader scalp coverage and is used for 30 minutes every other day.


The 272 Elite XL offers the same strong 272-diode coverage but is designed for those who need a larger 24.5" fit. It is a great choice for moderate thinning when a standard-size cap feels too snug.


The 272 DualWave is best for those who want a shorter daily treatment and dual-wavelength technology. It combines 650nm and 808nm wavelengths in a flexible design and requires just 6 minutes of use per day.


The 302 UltraFlex is a premium choice for those with more noticeable or widespread thinning who want greater diode coverage across the scalp. Its flexible design provides comfortable, full-scalp coverage with a convenient 6-minute daily treatment.


The 312 DualWave is our most advanced option, combining our highest diode count with dual-wavelength technology and full-scalp coverage. It is best for those who want the most comprehensive Kiierr treatment available with just 6 minutes of daily use.

What are the wavelengths, nanometers, power output, laser type, and EMF levels?

Models & specs

Kiierr uses medical-grade Class 3R laser diodes, not LEDs. Each diode delivers 5mW of power.


  • 148 Pro: 148 diodes | 650nm | 740mW

  • 272 Premier: 272 diodes | 650nm | 1,360mW

  • 272 Elite XL: 272 diodes | 650nm | 1,360mW

  • 272 DualWave: 272 diodes — 252 at 650nm + 20 at 808nm | 1,360mW

  • 302 UltraFlex: 302 diodes | 650nm | 1,510mW

  • 312 DualWave: 312 diodes — 272 at 650nm + 40 at 808nm | 1,560mW


We report nanometers and milliwatts rather than joules/cm² because joules/cm² is a calculated value that can vary depending on treatment area, distance, exposure time, and how each company calculates it.


What about EMF? Kiierr caps do not emit harmful levels of EMF. Hair-growth treatment is delivered through the laser diodes, while any low-level electrical or RF activity is related only to normal device operation.

What are the dimensions of the laser caps? Will the cap fit me?

Models & specs

Dimensions (L × W × H):

  • 148 Pro & 272 Premier: 7.25" × 7.5" × 3.5"

  • 272 Elite XL: 7.5" × 8.5" × 4.75"


Standard caps fit heads up to 23.5" in circumference, while XL/Elite models fit up to 24.5". The DualWave models and 302 UltraFlex feature a flexible design that contours and flexes slightly for comfort but is still designed for heads up to 23.5". Other models have a more rigid cap structure.


The cap does not need to fit perfectly snug to be effective. It may sit slightly higher on the head or have some space around the sides or back without affecting your treatment results.

What exactly is DualWave technology?

Models & specs

DualWave technology uses 2 wavelengths of laser light—650nm and 808nm—to target the scalp at different depths.


The 650nm red-light wavelength focuses closer to the surface of the scalp and hair follicles, while the 808nm near-infrared wavelength penetrates deeper into the scalp. Together, they provide a broader range of light exposure designed to help stimulate hair follicles, support cellular energy and encourage healthier, stronger hair growth.

Can I use Kiierr before or after a hair transplant?

Models & specs

Yes. Low-level laser therapy is commonly used before and after hair transplant procedures to support the scalp, promote healthy follicle activity, and help maximize overall results. Some clinical guidance recommends continuing LLLT through the transplant period and long term afterward.


After a transplant, Kiierr can also help support your existing, non-transplanted hair, which may continue to thin over time. Maintaining those follicles may help preserve your overall density and potentially reduce or delay the need for additional transplants in the future.


Always follow your surgeon’s instructions on when to resume wearing your Kiierr cap after surgery to avoid disturbing newly implanted grafts.

What is LLLT and how does it work?

LLLT science

LLLT stands for Low-Level Laser Therapy, a non-invasive technology that uses specific wavelengths of laser light to stimulate hair follicles at the cellular level.


The light is absorbed by cells in the scalp, helping support cellular energy production, circulation, and follicle activity. This can help move weakened follicles into a healthier growth phase, extend the active growth cycle, and support thicker, stronger, healthier-looking hair over time.

Is LLLT the same as red light therapy?

LLLT science

Yes. LLLT is a form of red light therapy, but not all red light therapy devices are the same.


Kiierr uses PureLaser™ Technology, which relies on medical-grade laser diodes rather than standard LEDs. Laser diodes deliver focused, consistent wavelengths of light directly to the scalp, which is why they are commonly used in clinical hair-growth devices.


So while Kiierr falls under the broader category of red light therapy, its technology is specifically designed for hair follicle stimulation and hair growth.

Have Kiierr laser caps been clinically studied?

LLLT science

LLLT for hair growth has been extensively studied in peer-reviewed clinical research, with studies showing significant improvements in hair density and growth for both men and women.


While every individual Kiierr model has not undergone its own separate clinical trial, our 272 Premier uses the same core specifications and laser technology studied extensively in LLLT hair-growth research. Our newer models build on this established technology and are FDA-cleared medical devices, though they have not each been individually studied.


In addition to the published research behind LLLT, our own customer survey data shows that over 90% of Kiierr users report seeing an improvement in their hair.

Can laser caps cause hair loss or cancer?

LLLT science

Laser caps do not cause permanent hair loss. Some users may experience temporary shedding when beginning LLLT, as older or weakened hairs shed and follicles transition into a healthier growth cycle. This does not happen to everyone and is temporary.


LLLT is considered safe and is FDA-cleared for hair growth. There is no evidence that properly used low-level laser therapy causes cancer. However, if you are extremely light-sensitive, taking photosensitizing medications, or currently undergoing cancer treatment, we recommend speaking with your doctor before use.

Do physicians recommend LLLT?

LLLT science

Yes. LLLT is widely used and recommended by physicians, hair restoration specialists, and other clinicians as a non-invasive treatment option for hair thinning and hair loss.


Today, more than 1,000 clinicians across the U.S. recommend Kiierr to their patients. LLLT can be used on its own or alongside other hair restoration treatments, depending on the individual’s needs.

When can I expect results while using a laser cap?

Results & treatment

Hair growth cycles vary by person. During months 0–3 you may experience some light shedding as weak hairs make way for stronger growth. Visible thickening and regrowth typically begin around months 3–6. The most noticeable results generally appear between 6–12 months. The greatest results are typically seen at 24 months and beyond with continued use.

What if I miss a session?

Results & treatment

Missing an occasional session is not a setback. Simply resume your normal schedule. Do not try to double up sessions to compensate — always stick to the prescribed frequency.

Do I need to continue using the cap forever?

Results & treatment

Hair loss is a progressive condition. After the initial treatment period (4–12 months), we recommend continuing sessions 1–2 times per week as a maintenance regimen. If you stop treatment entirely, hair loss may gradually return as the underlying cause (genetics, DHT) is still present.

Can I use other hair loss treatments alongside Kiierr?

Results & treatment

Yes. Kiierr can be used on its own or alongside other hair-growth treatments. Our Kiierr Shampoo, Multi-Peptide Serum, and Hair Growth Gummies are all great options to complement your laser cap by supporting scalp health, hair strength, and overall growth.


Some customers also use minoxidil or finasteride with Kiierr. If you already use one of these treatments, you can generally continue using it as directed by your doctor. However, we do not recommend starting a medication solely because you are beginning Kiierr if you are not already using one.


Other options include PRP treatments, microneedling, and hair transplants. These may provide additional benefits, but they can be more expensive, invasive, or require ongoing professional treatment. Kiierr offers a drug-free, non-invasive option that can also be combined with these approaches when appropriate.

Does Follicle Revival DHT Blocking / Daily Density Shampoo work on its own?

Products

Yes, Follicle Revival DHT Blocking Shampoo (also known as Women's Daily Density Shampoo) can be beneficial on its own, especially for improving scalp health, reducing buildup, supporting stronger-looking hair, and helping create a healthier environment for growth.


For more noticeable or advanced hair thinning, however, we recommend a multi-faceted approach. Hair loss often has multiple contributing factors, so combining treatments can address more than one part of the problem.


For example, some customers may see improvement using the shampoo + conditioner + Multi-Peptide Serum, while our most comprehensive routine is:

Kiierr Laser Cap + Follicle Revival Shampoo + Multi-Peptide Serum + adequate vitamins/nutrition


The cap directly stimulates the follicles with LLLT, while the shampoo supports the scalp and helps manage DHT-related factors, the serum delivers targeted topical ingredients, and proper nutrition supports healthy hair production from within.


This does not mean the shampoo is ineffective by itself—it simply means that combining complementary treatments can provide stronger overall support, especially when hair loss is more advanced.

Do I need to use other products for the cap to work?

Products

No. Kiierr laser caps are designed to work as a standalone hair-growth treatment and do not require shampoo, serums, supplements, or medications to be effective.


However, hair loss can have multiple contributing factors, so some customers choose a multi-faceted approach for additional support. Combining your cap with Follicle Revival DHT Blocking Shampoo, Multi-Peptide Serum, and adequate vitamins/nutrition can support scalp health, follicle activity, and healthy hair from multiple angles.


Think of these products as complementary—not required. The laser cap remains the foundation of the treatment.

How long does shipping take?

Shipping

Most products ship within 2–3 business days, but processing time can vary by product.


Note: The Elite XL take approximately 7–10 business days. The 272 DualWave and 312 DualWave are in presale and require about 1–2 weeks to process before shipping.


US delivery typically takes 2–3 business days after shipment. International delivery typically takes 3–5 business days after shipment, though customs can affect this.

What are the shipping costs?

Shipping

Shipping is completely free for all US orders. International shipping costs approximately $50–$55 USD (for laser caps) depending on destination. International shipments may also be subject to duties, taxes, or import fees charged by FedEx or your country's customs office — these are the customer's responsibility.

Where do you ship to?

Shipping

Kiierr ships to most countries worldwide via FedEx. At this time we are unable to ship to Germany, Spain, Mexico, Turkey, or Greece. If you have an address in another eligible country, we can ship to that address instead.

My order says delivered but I didn't receive it — what do I do?

Shipping

First check around your delivery area (porch, mailbox, neighbor) and confirm your shipping address was correct. Carriers sometimes mark packages as delivered slightly early. If the package doesn't appear within 24 hours, contact your local post office — carriers have GPS scanners and can locate the exact delivery point. If still unresolved, email service@kiierr.com with your order and tracking number.

Can I modify or cancel my order after placing it?

Shipping

If your order hasn't shipped yet, we may be able to make changes. You can submit a request at the top of this page. Once an order has shipped, it can no longer be modified or canceled. If you wish to cancel after shipping, you may refuse the package at delivery — a $50 restocking fee applies for packages returned to sender unopened.

What is your return policy?

Returns & guarantee

Laser Caps & Combs: Covered by our 7-Month Growth Guarantee. Register within 45 days of delivery, use the device consistently for 210 days, and contact us between days 210–240 if you do not see improvement. A 25% return fee applies unless you provide 7 monthly progress photos/videos.


Shampoos, beauty products & other eligible products: Covered by our 90-Day Guarantee with no registration required. Use the product consistently for 90 days, and if you do not see improvement, contact us within 7 days of the 90-day mark to request a return. Products returned under the 90-Day Guarantee cannot be reordered for the same customer, email address, or shipping address.

Can I return my cap before 7 months?

Returns & guarantee

Returns under the growth guarantee are only accepted after 7 months (210 days) of consistent use. LLLT requires long-term use to produce results — many customers don't see significant changes until months 5–7. For special medical circumstances, contact our support team to discuss available options.

What if I didn't register my device in time?

Returns & guarantee

Registration within 45 days with a before photo is a required condition of the growth guarantee. Without confirmed registration on file, we are unable to process a return under this policy. If you believe you may have registered under a different email, contact service@kiierr.com and we'll look it up.

What payment methods do you accept?

Payment

Kiierr accepts all major payment methods through Shopify, including credit and debit cards, PayPal, and Shop Pay. You can also use your FSA or HSA account for reimbursement. Financing options are available at checkout for eligible customers.

Can I use my FSA or HSA to pay?

Payment

Yes — as an FDA-cleared medical device, Kiierr laser caps are generally eligible for FSA/HSA reimbursement. Choose TrueMed at checkout.

Do you offer financing or payment plans?

Payment

Yes — Kiierr offers financing through third-party providers at checkout. Eligible customers can split their purchase into monthly installments. Financing options appear during the checkout process at kiierr.com.

What does the 2-year warranty cover?

Account & warranty

Every Kiierr laser cap includes a 2-year warranty from the date of purchase covering factory defects and workmanship errors. It does not cover damage from misuse, unauthorized modifications, use with non-Kiierr accessories, or normal wear and tear.


A $29.99 battery replacement fee will be charged for batteries replaced during the 2 year warranty period. After the warranty ends, a battery replacement is $99.

Where do I send my cap for warranty repair?

Account & warranty

Once you submit a warranty claim, return instructions will be provided. Do NOT return any items without official approval as they will be refused at delivery.

How do I purchase a replacement battery, cord, or charger?

Account & warranty

All replacement parts are available here.

How do I manage or cancel my auto-ship subscription?

Account & warranty

Log into your account here and navigate to the Subscriptions section to manage, pause, or cancel.


You can also email service@kiierr.com for assistance.


Changes must be made at least 48 hours before your next renewal date to avoid being charged for the upcoming shipment.

Can I use the cap on wet hair?

Device & safety

No — always use the cap on completely dry hair. The cap is an electronic device that can be damaged by moisture, and wet hair blocks laser light from reaching the scalp. Using the cap on wet hair can cause electrical damage and will void your warranty.

Can I use the cap on color-treated or chemically processed hair?

Device & safety

Yes — color, bleach, relaxers, perms, and other chemical treatments do not interfere with LLLT. Ensure hair is clean and fully dry before each session. Avoid using the cap if your scalp has open sores or active irritation from a recent chemical treatment.

Can I travel with my Kiierr cap?

Device & safety

Yes — the cap and battery can be packed in carry-on or checked luggage and is TSA-friendly. The power supply adapts to both US (110V/60Hz) and international voltages, but you may need a plug adapter specific to your destination. Do not use non-Kiierr chargers even with a plug adapter.

Do I need to worry about eye safety?

Device & safety

The Kiierr cap is a Class 3R laser device. Always avoid direct eye contact with the laser diodes. Place the cap on your head before turning it on — never look directly at the lasers while powered on.

Can I use the cap if I have a pacemaker or implanted device?

Device & safety

There are no known contraindications with using a laser cap with an internally implanted pacemaker, defibrillator or ICD device. However, we always receive checking with your doctor if you have specific health concerns.

I'm experiencing headaches when using the cap — what should I do?

Device & safety

The laser cap works by increasing blood flow to the scalp. Some users are more sensitive to this effect. Try cutting your session time in half (15 minutes every other day for 30-minute models; 3 minutes daily for 6-minute models) — you can still see results. Contact our support team if headaches persist.

How do I clean my Kiierr cap?

Device & safety

Wipe the inside of the cap with a slightly damp cloth and allow to air dry completely before storing or using again. Do not submerge in water or machine wash. Avoid harsh chemicals or alcohol-based cleaners on the laser diode surface.