Industrial Lighting Solutions UV-HCM-350 Honeywell Humidifier HWM-500 UV Germicidal E17 Bulb Eliminates bacteria contamination and bacteria growth Easy to install Used in including 100% compatible with the Honeywell HCM350, HCM 350, HCM-350-UV, HMW 500, HWM500 UV E14/E17 base