Model:ZW4D15W-Z134,ZW4D15W-Z235, ZW12D15W-Z287,ZW16D15W-Z345, ZW25D15W-Z565,ZW30D15W-Z885, ZW35D15W-Z925,ZW55D15W-Z925 Tube diameter:15MM Lamp length s(mm):134,215,287,345,565, 885,925,925 Power:4w,6w,12w,16w,25w,30w,35w,55w Tube vottage(v):18-19,30-31,35-36, 39-40,70-75,120,100,130 Tube fountain: 180mA,190mA,290mA,300mA, 300mA,225mA,300mA,250mA UV density(μw/cm2):9,17~20,36~37,44, 85,110,115,117 Features: Not cathode, pre-heat stars; The rated average useful life is 8000 hours