Metal Halide Lamp, 65, 4200 K, 19100 LM (Horizontal);20800 LM (Vertical) Brightness (Lumens), 250 W, Clear, Hard Glass Material, 6000 H (Horizontal);10000 H (Vertical) Average Life, Mogul Base, M58 Ansi Ballast Code, Non Dimmable, 3.5 In Diameter, 8.25 In Height, 31 % Mercury Content, 5.55 LB