LSE Lighting Replacement UV UV-C Bulb for Treatment Services Model ATS4-450 Brand: LSE Lighting Length: 17.71" - Provides Superior Water Purification Base: 4Pin T5 Ceramic Base [4pin on ONE End] Fits MODELS: SL-8V, EV-8E, DWS-8V, SE-8V All lamps listed are compatible LSE Lighting brand UV products. We do not sell ATS brand lamps. All ATS brand names, trademarks and logos are property of ATS.