... : Electronic Ballast, Dimmable Electronic Ballast, Grow Light Ballast 400W, Hydroponic grow ballast 400w, electronic ballast 400w, 110V, UL Listed1) Input Voltage Range: 120V, ... crest factor: <1.5 7) Max. Lamp distance from ballast: 15m/49ft 8) Ambient temperature: -25 ~ +50 ... Perfect protection and monitoring function A) Built-in voltage monitoring function B) Trouble-detecting protection function 3) ...