LumaPro(R), Magnetic, HID Ballast Kit, Ballast Start Type Pulse, ANSI Code M138, M153, Metal Halide Ballast Bulb Type, Number of Bulbs Supported 1, Max. Bulb Watts 250 W, Input Voltage 120 to 277V AC, Input Watts 284 W, -20 Degrees F Min. Starting Temp., Ballast Factor 0.97, Frequency 60 Hz