Advance 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 291 W -20 Degrees F Min Starting Temp Ballast Factor 1 Frequency 60 Hz