Mark 7(R) 0-10V, Electronic, Fluorescent Ballast, Ballast Start Type Programmed, Input Voltage 120 to 277V AC, Number of Bulbs Supported 2, Max. Bulb Watts 28 W, Ballast Bulb Type T5, Dimming Yes, Dimming Type Full Continuous Dimming, Dimming Method 0-10V, Dimming Range 100 Percent to 3 Percent, Min. Starting Temp. 50 Degrees F