Advance, Magnetic, HID Ballast, Ballast Start Type Pulse, ANSI Code M140, M90, Metal Halide Ballast Bulb Type, Number of Bulbs Supported 1, Max. Bulb Watts 100 W, Input Voltage 120/277V AC, Input Watts 125W, -20 Degrees F Min. Starting Temp., Ballast Factor 1, Frequency 60 Hz