Pulse Start Metal Halide Base Up, Bulb Base Type Mogul Screw (E39), Bulb Dia. 3 1/2 in, Bulb Housing Glass, Bulb Shape ED28, Color Rendering Index 65, Color Temperature 4300K, Lumens 21,375 lm, Light Technology Metal Halide, Overall Length 8 3/8 in, Shatter- No, Voltage 147V, Watts 250 W, Bulb Beam Angle 360 Degrees , Bulb Finish Clear, Rated Life 15,000 hr, ANSI Code M153/M138/E, Dimmable No, For Enclosed Fixtures No, Bulb Operating Position Vertical Base Up +/-15 Degrees