Description
Kernel KN4003BL 311 nm Phototherapy — Key Facts
- Type: Corded handheld narrowband UVB lamp (corded handheld)
- Wavelength: 311 nm
- Treats: Psoriasis, vitiligo, eczema, atopic dermatitis & related skin conditions
- Best for: At-home spot treatment
- Price: $288 | financing available
Frequently Asked Questions
What is the KN4003BL used for?
The KN4003BL is a 311 nm corded handheld 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 KN4003BL cost and where can I buy it?
The Corded, Handheld 311nm UVB Lamp - Light Therapy for Psoriasis or Vitiligo on Scalp, Face, Neck, Hands and Feet is $288 at HeyMedSupply.com, with financing available. HeyMedSupply is a U.S.-based medical supply retailer that ships nationwide.
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, parapsoriasis, pityriasis rosea & mycosis fungoides | 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
- Delivery:
- Free shipping 2 - 3 Days
- Application:
- Psoriasis, Vitiligo, Eczema, Pityriasis Rosea, Atopic Dermatitis
- Treatment Area:
- Scalp, Face, Hands and Feet
- Brand Name:
- Kernel
- Product:
- Corded, Handheld 311nm Narrowband UVB Lamp
- Model:
- KN4003BL
- 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:
- Corded
- Built-in Battery:
- N
- Power Source:
- 110V (60Hz)
- Screen:
- Basic LED Screen
- Light Source Lifespan:
- ≤ 500h
- Packing List:
- 1 x KN4003BL, 1 x UV-proof Goggles, 1 x Charging Cable, 1 x User Manual
- Dimension:
- 12.48'' L × 2.05'' W × 1.89'' H
- Product Weight:
- 1.63 lbs
Product Videos
Reviews
27 Reviews
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It arrived in two days!
The delivery is fast and well-packed. I use it to treat eczema between my fingers, on my knuckles, and palms. I try to avoid steroid creams as much as possible, so UVB therapy has been a great alternative.
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Recommend
It’s worth the price I paid. I’ve been using it for plaque psoriasis since April, and some of the raised, red, inflamed skin around my hairline has cleared up. The dead scales on those patches first darkened and hardened, then gradually fell off as new skin formed after two-month of treatment. The process is slow, but it’s working. You need to be consistent and patient.
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It definitely works!
I got this to treat the eczema on my elbows, which was itchy and sometimes painful, especially during the summer. Since purchasing it in April, I’ve been using it consistently, and I can confidently say that there’s been significantly less rash compared to the same time last year.
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Would recommend
I started using this device after my dermatologist recommended narrowband UVB therapy for my vitiligo. I’ve been treating my hands and face 3 times a week, and after 3 months, there’s already noticeable repigmentation.
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Good enough
The delivery was quick. Let's try it out!
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Affordable option
The eczema on my fingers, elbows, and the hollows behind my knees has been getting itchier as the weather gets hotter. I’m applying lotion regularly, and I’m hopeful that this lamp will bring some relief. I plan to stick with the treatment three times a week throughout the summer to see what kind of difference it makes.
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The delivery only takes 2 days!
The package arrived in great condition, and I was pleasantly surprised to find a quality examination card included, showing that the device was tested before shipping.
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Will try this first.
I decided to start with this entry-level device before investing in a more high-end model. It’s a great.
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Super fast shipping
The package was delivered on Saturday, faster than I expected, especially since they mentioned it had to be shipped from the manufacturer. It arrived in great condition, and everything was well-packaged.
