GE Current Magnetic Core and Coil Ballast Kit, Replacement, HID Metal Halide Lamp, 400 W Lamp, 436 W Wattage, 480 VAC, 3.7 A, 60 Hz Frequency, -30 deg C Minimum Starting, Power Factor: 0.9%, 1 Lamp, Ballast Factor: 1, Panel Mounting, 4-3/4 in L x 4-1/4 in W Dimensions