UltraStart(R), Electronic, Fluorescent Ballast, Ballast Start Type Programmed, Input Voltage 120 to 277V AC, Number of Bulbs Supported 4, Max. Bulb Watts 54 W, Ballast Bulb Type T5, Dimming Yes, Dimming Type Step Dimming, Dimming Method Proprietary, Dimming Range 100 Percent/30 Percent, CA Title 20 Compliant Yes, Min. Starting Temp. 0 Degrees F