Description
Kernel KN4003BL2D 311 nm Phototherapy — Key Facts
- Type: Portable narrowband UVB lamp (portable handheld)
- Wavelength: 311 nm
- Treats: Psoriasis, vitiligo, eczema, atopic dermatitis & related skin conditions
- Best for: At-home spot treatment
- Price: $319 | financing available
Frequently Asked Questions
What is the KN4003BL2D used for?
The KN4003BL2D is a 311 nm portable narrowband UVB lamp for phototherapy of psoriasis, vitiligo, eczema and related skin conditions. It is designed for at-home spot treatment.
How is a 311 nm UVB lamp different from a 308 nm excimer device?
A 311 nm narrowband UVB lamp treats larger body areas at a comfortable intensity — good for widespread psoriasis, vitiligo or eczema. A 308 nm excimer device targets small stubborn patches at higher intensity. This 311 nm lamp is suited to broader at-home phototherapy.
How much does the KN4003BL2D cost and where can I buy it?
The Portable 311nm UVB Lamp for Psoriasis, Vitiligo and Eczema on Scalp, Face, Hands and Feet is $319 at HeyMedSupply.com, with financing available. HeyMedSupply is a U.S.-based medical supply retailer that ships nationwide.
Important Safety Information
This is a medical phototherapy device intended for use under the guidance of a healthcare provider. Consult your physician before beginning treatment.
Do not use this device if you have or have had:
- A history of skin cancer or a family history of melanoma
- A photosensitive condition such as lupus erythematosus or porphyria
- A known sensitivity to ultraviolet (UV) light
Consult your physician before use if you:
- Are taking photosensitizing medications (e.g., certain antibiotics, diuretics, retinoids, or St. John’s Wort)
- Are pregnant or nursing
- Have a condition affecting the skin, eyes, or immune system
When using this device:
- Always wear the UV-protective eyewear provided; never look directly at the light source
- Follow prescribed exposure times exactly — overexposure can cause burns
- Apply only to intact skin; do not use on broken or damaged skin
This product has not been evaluated to treat any condition other than those for which it is FDA-cleared. Statements herein are not intended to diagnose, treat, cure, or prevent any other disease.
Comparison Chart
| Specification | KN4003BL | KN4003BL2D | KN4006B | KN4006BL1D | KN5000C |
|---|---|---|---|---|---|
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| Name | Corded, Handheld 311nm UVB Lamp | Portable 311nm UVB Lamp | Stationary & Handheld Dual-Bulb 311nm UVB Lamp | Cordless, Dual-Bulb 311nm UVB Lamp, 2X Coverage | 308nm Excimer Laser – Highest Intensity and Precision |
| Setting | Home & domestic travel | Home, domestic & international travel | Home | Home, domestic & international travel | Clinics & home |
| Price | $288.44 | $319.00 | $365.00 | $369.00 | $2,700.00 |
| Application | Psoriasis, vitiligo, eczema, atopic dermatitis | For patients with a longer history of more severe conditions who have not seen improvement from other options | |||
| Ideal for Areas | Scalp & hairline Face & neck Hands & feet |
Scalp & hairline Face & neck Hands & feet |
Stationary: Hands & feet Detached: Shoulders, limbs & torso |
Face & neck Hands & feet Shoulders Torso & limbs |
Entire body, especially skin folds like elbows, eyelids, armpits, fingers, knees & toes |
| Treatment Speed | Fast | Fast | 1.2X Faster | 1.2X Faster | 11X Fastest |
| Lamp Intensity | 4.5 mW/cm² | 4.5 mW/cm² | 5.5 mW/cm² | 5.5 mW/cm² | 50 mW/cm² |
| Light Source | 1 × 311nm Bulb | 1 × 311nm Bulb | 2 × 311nm Bulbs | 2 × 311nm Bulbs | 308nm XeCl Excimer Laser |
| Treatment Size | 8.5 in² | 8.5 in² | 16 in² | 16 in² | 3.1 in² |
14-Day Return Policy
- Customers may return eligible products within 14 days of delivery for a refund or exchange.
- For hygiene and safety reasons, opened or used products cannot be returned unless defective or faulty.
- A 20% restocking fee applies to all returns except defective. We will repair, replace, or refund defective items free of charge.
- For full details, please refer to Return Policy under the Warranty tab.
Warranty Information
UVB Lamps – Warranty & Return
Product Warranty
- 1-year warranty on the device
- 500-hour warranty on the UV light source
- Includes free parts, replacements, and shipping for manufacturer defects
- Post-warranty repairs may be arranged through Hey Med Supply
This warranty complies with the Magnuson–Moss Warranty Act, which requires that all terms be clearly disclosed.
14-Day Return Policy
- Returns accepted within 14 days of delivery for a refund or exchange.
- Opened or used products cannot be returned unless defective.
- A 20% restocking fee applies to all returns except defective.
- We will repair, replace, or refund defective items free of charge.
Eligible Returns
- Sealed & Unused: The device, original packaging, and all accessories (including user manual and UV-protective glasses) must be in new, unused, and undamaged condition.
- Defective or Damaged: Products that arrive defective or damaged may be returned, even if opened, as long as the issue is reported within 14 days.
Ineligible Returns
We are unable to accept returns if:
- The return is not authorized in advance
- The request is made after 14 days of delivery
- The return is shipped back more than 5 days after receiving authorization
- The product is no longer in “new” condition, including:
- Devices that are damaged
- Missing or damaged original packaging
- Missing or damaged accessories
- Retail packaging with shipping labels or markings applied directly
How to Return
- Initiate a Return
- Contact our team via email or through our website within 14 days of delivery.
- Complete the return form. Reply to your order confirmation email with the form attached, along with any additional details you'd like to share.
- Receive Authorization
- We will respond within 24 hours with approval and return instructions.
- Unauthorized returns will not be accepted.
- Ship Back the Product
- Repack the item with all original components and undamaged, original packaging.
- Place the product box inside a separate shipping box for protection during transit.
- Do not apply labels directly to the product packaging.
- Ship the return within 5 business days of receiving authorization.
- Customers are responsible for return shipping unless the item is defective or damaged.
- Receive Refund
- Refunds are processed within 48 hours of return inspection.
- We reserve the right to refuse returns showing signs of misuse or wear.
- Please allow 2–3 business days for the refund to appear in your account.
- Returns that do not meet our policy criteria may be declined.
Regulatory Compliance
Hey Med Supply complies with all relevant U.S. consumer protection and FDA regulations, including:
- Magnuson–Moss Warranty Act (clear warranty terms and dispute resolution)
- FDA Quality System Regulation (21 CFR Part 820) (device servicing and safety)
- 21 CFR Part 806 (reporting of medical device corrections or recalls)
- Applicable state laws requiring conspicuous return policy disclosures
Product Details
- Application:
- 311nm UVB Phototherapy
- Delivery:
- Free shipping 2-3 Days
- Treatment Area:
- Scalp, Face, Hands and Feet
- Brand Name:
- Kernel
- Product:
- Cordless, Portable 311nm Narrowband UVB Lamp
- Model:
- KN4003BL2D
- Certificate:
- FDA Approved
- Wavelength:
- 311 nm ± 3 nm
- Light Source:
- 1 x Philips Light Bulb
- Light Intensity:
- 4.5 mw/cm2
- Treatment Size:
- 8.5 in² ± 10%
- Treatment Speed:
- Fast
- Treatment Mode:
- Time
- Work Distance:
- 1.18 in ± 0.20 in
- Built-in MED Test:
- N
- Mobility:
- Portable
- Built-in Battery:
- Y
- Battery Life after Fully Charged:
- 70 min
- Power Source:
- Adaptable to Voltage Range 100-240V
- Screen:
- Basic LED Screen
- Light Source Lifespan:
- ≤ 500h
- Packing List:
- 1 x KN4003BL2D, 1 x UV-proof Goggles, 1 x Charging Cable, 1 x User Manual
- Dimension:
- 12.99'' L × 2.28'' W × 1.83'' H
- Product Weight:
- 1.98 lbs
Product Videos
Reviews
26 Reviews
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The cordless works great!
I compared several models but ultimately chose this cordless version for its convenience. After about 30 sessions (3 months), I’ve noticed that the flaky skin on my scalp and elbows has smoothed out. The patches on my neck and arms have been healing more slowly, but I’m still really happy with the progress. Even though it takes time, I prefer light therapy over oral medications. Definitely worth trying.
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It Worked!
The psoriasis on the back of my neck and behind my ears flared up because I didn't apply enough sunscreen, so I started looking for a way to speed up the healing process. Thankfully, I found this UVB lamp, and after nine sessions, the irritation has started to calm down. I’ll continue using it to further improve my skin!
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Works great!
Pros: Portable and lightweight. My arm doesn’t feel sore even after holding it up to treat my vitiligo spots on my cheeks, lips, and around my eyes. After two months of use, we’ve seen obvious improvements in those areas—less pigmentation than before, especially around my mouth. Very happy with the results! Cons: I wish the light were stronger for faster results and that the lamp were smaller to better target affected areas while protecting healthy skin.
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Easy to use.
I wasn't sure how to use it at first, but thankfully, the customer service team guided me through the process. To get the best results, you’ll need to adjust your treatment time—increasing, maintaining, or decreasing it based on how your skin reacts. Hopefully one day they can upgrade the design and people set the dose directly on the machine.
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Psoriasis on scalps and forehead
You need to be patient and consistent to see improvements in your skin, but once they appear, you’ll know the time was well worth it! The itchy, dry skin on my hairline and forehead has significantly improved, and I feel so much relief.
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Recommend!
This machine is not a facade. It achieve the same result as I did at the doctor’s office. I have used it for 3 months to treat the skin behind my ear because of it's portable. The size of red spots behind my ears reduced and less swollen.
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Scalp machine
This comb has been really helpful in treating the psoriasis on my scalp, thanks to the comb attachment. It also helps me maintain the right distance for effective use. I've noticed a reduction in dandruff and itching in only two months!
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Portable. Handheld is well made
The device is easy to use for treating spots on the back of my neck and near the scalp because it's portable. I have completed 15 sessions following the user manual and already feel much better. The irritation and pain have decreased. Customer Service cares a lot. My package wasn’t delivered without a signature requirement the first day. They proactively worked with DHL for me before I even reached out.
