Advance Mark 7 0-10V Dimmable Fluorescent Ballast, D-Can, T5HO Lamp, 54 W Lamp, 16 to 118 W Wattage, 120 to 277 V AC, 0.38 to 0.91 A, 50/60 Hz Frequency, Programmed Start, 10 deg C Minimum Starting, Total Harmonic Distortion: 10%, Power Factor: 0.98, Yes Dimmable, 2 Lamps, Thermal Protection: Class P, Ballast Factor: 1, 70 deg C, Metal, 16.7 in L x 1.18 in W x 1 in H Dimensions