Klär Lite (RCW-KL1000)

{0} FDA U.S. FOOD & DRUG ADMINISTRATION March 4, 2026 Radcliffe Watts, LLC Dan Smith Chief Executive Officer 201 E 5th St. Mansfield, Ohio 44902 Re: K253871 Trade/Device Name: Klär Lite (RCW-KL1000) Regulation Number: 21 CFR 878.4630 Regulation Name: Ultraviolet Lamp For Dermatologic Disorders Regulatory Class: Class II Product Code: FTC Dated: November 23, 2025 Received: December 4, 2025 Dear Dan Smith: We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading. If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register. {1} K253871 - Dan Smith Page 2 Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download). Your device is also subject to, among other requirements, the Quality Management System Regulation (QMSR) (21 CFR Part 820), which includes, but is not limited to, ISO 13485 clause 7.3 (Design controls), ISO 13484 clause 8.3 (Nonconforming product), and ISO 13485 clause 8.5 (Corrective and preventative action). Please note that regardless of whether a change requires premarket review, the QMSR requires device manufacturers to review and approve changes to device design and production (ISO 13485 clause 7.3 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181). Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the Quality Management System Regulation (QMSR) (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050. All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems. For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory- {2} K253871 - Dan Smith Page 3 assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100). Sincerely, TANISHA L. HITHE -S Digitally signed by TANISHA L. HITHE -S Date: 2026.03.04 15:46:19 -05'00" Tanisha Hithe Assistant Director DHT4A: Division of General Surgery Devices OHT4: Office of Surgical and Infection Control Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health Enclosure {3} K här Lite Page 9 of 44 | Indications for Use | | | | --- | --- | --- | | Please type in the marketing application/submission number, if it is known. This textbox will be left blank for original applications/submissions. | K253871 | ? | | Please provide the device trade name(s). | | ? | | Klär Lite (RCW-KL1000) | | | | Please provide your Indications for Use below. | | ? | | The Klär Lite is an Ultraviolet Light Emitting Medical Device. It is intended for use in localized phototherapeutic treatment of dermatologic conditions such as psoriasis, vitiligo, atopic dermatitis (eczema), seborrheic dermatitis and leukoderma on all skin types (I-VI). | | | | Please select the types of uses (select one or both, as applicable). | ☑ Prescription Use (Part 21 CFR 801 Subpart D) ☐ Over-The-Counter Use (21 CFR 801 Subpart C) | ? | {4} 510(k) #: K253871 510(k) Summary Prepared on: 2025-12-04 | Contact Details | 21 CFR 807.92(a)(1) | | --- | --- | | Applicant Name | Radcliffe Watts, LLC | | Applicant Address | 201 E 5th St Mansfield OH 44902 United States | | Applicant Contact Telephone | 714-292-5532 | | Applicant Contact | Mr. Daniel Smith | | Applicant Contact Email | admin@radcliffewatts.com | | Device Name | 21 CFR 807.92(a)(2) | | Device Trade Name | Klär Lite (R CWKL10®) | | Common Name | Ultraviolet lamp for dermatologic disorders | | Classification Name | Light, Ultraviolet, Dermatological | | Regulation Number | 878.4630 | | Product Code(s) | FTC | | Legally Marketed Predicate Devices | 21 CFR 807.92(a)(3) | | Predicate # | Predicate Trade Name (Primary Predicate is listed first) | | Product Code | Flowering | | K170489 | Clarify Medical Phototherapy System | | | FTC | | Device Description Summary | 21 CFR 807.92(a)(4) | | The Klär Lite is a narrowband UVB light emitting phototherapy medical device intended for treatment of dermatologic conditions such as psoriasis, vitiligo, atopic dermatitis (eczema), seborrheic dermatitis and leukoderma on all skin types (I-VI). | | | Intended Use/Indications for Use | 21 CFR 807.92(a)(5) | | The Klär Lite is an Ultraviolet Light Emitting Medical Device. It is intended for use in localized phototherapeutic treatment of dermatologic conditions such as psoriasis, vitiligo, atopic dermatitis (eczema), seborrheic dermatitis and leukoderma on all skin types (I-VI). | | | Indications for Use Comparison | 21 CFR 807.92(a)(5) | | The indications of use are the same between this device and predicate/reference devices. | | | Technological Comparison | 21 CFR 807.92(a)(6) | | Please reference the attached document. | | | Non-Clinical and/or Clinical Tests Summary & Conclusions | 21 CFR 807.92(b) | {5} The Klär Lite phototherapeutic device was evaluated through a comprehensive series of non-clinical tests to support a determination of substantial equivalence with the predicate device. ## Electrical and Mechanical Safety: Testing was performed in accordance with IEC 60601-1:2012 (Edition 3.1) Medical electrical equipment - Part 1: General requirements for basic safety and essential performance, and IEC 60601-1-11:2015 Medical electrical equipment — Part 1-11: General requirements for basic safety and essential performance — Collateral standard: Requirements for medical electrical equipment and medical electrical systems used in the home healthcare environment for home-use medical electrical equipment. All results demonstrated compliance with requirements for protection against electrical shock, mechanical hazards, fire, and thermal safety. ## Electromagnetic Compatibility (EMC): Conducted per IEC 60601-1-2:2014 (Edition 4.0) Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral Standard: Electromagnetic disturbances - Requirements and tests. The device met all emissions and immunity limits including ESD, radiated/conducted RF, EFT/Burst, Surge, Power Frequency Magnetic Field, and Voltage Dips/ Interruptions. ## Photobiological Safety and Performance: Evaluated per IEC 62471:2006 Photobiological safety of lamps and lamp systems and ISO 15004-2, confirming the emitted optical radiation is within safe exposure limits for intended therapeutic use. ## Biocompatibility: Evaluated per the ISO 10993 series (specifically ISO 10993-1, Biological evaluation of medical devices—Part 1: Evaluation and testing within a risk management process. Part 5: Tests for in vitro cytotoxicity, Part-10, Tests for skin sensitization, and Part-11: Tests for systemic toxicity. Tests confirmed the safety of all patient-contacting materials for intact skin contact, including cytotoxicity, sensitization, and irritation testing performed under GLP conditions. ## Software Verification and Validation: Conducted in accordance with IEC 62304:2006 + AMD 1:2015, Medical device software — Software life cycle processes, supporting software reliability and safety at the determined risk classification with basic level of documentation. ## Risk Management: Completed per ISO 14971:2019 Medical devices — Application of risk management to medical devices, to ensure identified hazards are effectively controlled and residual risk is acceptable. ## Labeling and Usability: Evaluated per IEC 62366-1:2015 EC 62366-1:2015 and validated through formative and summative usability studies. Collectively, these tests demonstrate that Klär Lite meets applicable FDA-recognized consensus standards. Clinical testing was not required to establish substantial equivalence for the Klär Lite phototherapeutic device. The results of all nonclinical verification and validation testing demonstrate that the Klär Lite phototherapeutic device is as safe and effective. Conclusion: The Klär Lite device is substantially equivalent to the predicate device in terms of safety, effectiveness, and performance. {6} | Feature | Predicate Device – Skylit Phototherapy System (K170489) | Subject Device – Klär Lite K253871 | Comparison Result | | --- | --- | --- | --- | | Technology Type | Narrowband UV-B LED phototherapy | Narrowband UV-B LED phototherapy | Identical | | Wavelength | 300-320 nm | 311 ± 2 nm (UV-B) (nominal peak within UV-B emission range 295-320 nm) | Comparable | | Light Source | LED array | LED array | Identical | | Output Irradiance | 3.0-15.0 mW/cm² | 3.0-5.0 mW/cm² | Within Predicate Range | | Treatment Area | 4.5 cm² | 5.08 cm x 5.08 cm | Comparable | | Exposure Control | Software-controlled timer and preset dose by skin type | Microcontroller algorithm with skin-type presets and real-time temperature feedback | Equivalent / Enhanced | | Safety Features | Optical filter, thermal shutdown, firmware interlocks | Optical filter, integrated thermal sensor with auto-shutdown | Comparable | | Applicator Type | Handheld home-use applicator with comb guide | Handheld home-use applicator with integrated diffuser | Equivalent | | Operating Modes | Preset and manual | Preset and manual with temperature-compensated dose control | Equivalent / Enhanced | | Cleaning Method | 70 % IPA wipe (per IFU) | Validated 70 % IPA wipe per (RFV-1010A, CEV-1010A, SLJ-1010A) – no material damage | Equivalent / Enhanced | {7} | Power Input | Rechargeable battery or DC supply | Medical-grade DC supply | Comparable | | --- | --- | --- | --- | | Software Classification | IEC 62304 Class B | IEC 62304 Class B | Identical | | Biocompatibility | ISO 10993 tested for skin contact | ISO 10993 tested for skin contact | Identical | | Electrical Safety | IEC 60601-1 Ed 3.1 | IEC 60601-1 Ed 3.1 | Identical | | EMC | IEC 60601-1-2 Ed 4.0 | IEC 60601-1-2 Ed 4.0 | Identical | | Photobiological Safety | IEC 62471 | IEC 62471 | Identical | | Usability Engineering | IEC 62366-1 | IEC 62366-1 | Identical | | Prescription Status | Rx-only | Rx-only | Identical |  Figure 1. Skylit Phototherapy System (K170489)  Figure 2. Subject Device - Klär Lite Phototherapy System