Advance HID Ballast, Magnetic, Metal Halide Lamp, 150 W Lamp, 185 W Wattage, 120/208/240/277 VAC, 1.6/0.96/0.8/0.7 A, 60 Hz Frequency, Pulse Start, -20 deg F Minimum Starting, Power Factor: 0.9, No Dimmable, 1 Lamp, Thermal Protection: Class P, 71A5492 Lamp Base, Ballast Factor: 1, ANSI M102/M142 Ballast Grade, 4 in L x 3.9 in W x 2.9 in H Dimensions