GE Current, Magnetic, Hid Ballast Kit, Ballast Start Type Pulse, ANSI Code M135/M155, Metal Halide Ballast Bulb Type, Number of Bulbs Supported 1, Max. Bulb Watts 400 W, Input Voltage 120 to 277V AC, Input Watts 400 W, -20 Degrees F Min. Starting Temp., Ballast Factor 1, Frequency 60 Hz