GE Multi-Vapor® Metal Halide Lamp, High Intensity Discharge, MVR400/U/ED28 Designation, 400 W Wattage, 540 VAC, Quartz Metal Halide Lamp, E39 Mogul Screw Lamp Base, ED28 Shape, 36000 Lumens, 20000 hr Average Life, 65 CRI, 4000 K Color Temperature, Clear Lamp, Enclosed Fixture, 3-1/2 in Dia x 8-1/4 in L Dimensions