Metal Halide HID Bulb, ED28 Bulb Shape, Mogul Screw (E39) Bulb Base Type, Metal Halide, 36,000 lm, Bulb Operating Position Universal Burning, 400 W, Trade Number MH400/U/ED28, Rated Life 20,000 hr, Standard Bulb Type, 4000K, 360 Degrees Bulb Beam Angle, 3 1/2 in Bulb Dia., 8 5/16 in Overall Length, Shatter-Resistant No, Bulb Finish Clear, Color Rendering Index 59, Bulb Minimum Starting Temperature -40 Degrees F