HID Bulb, Bulb Base Type Mogul Screw (E39), Bulb Dia. 3 1/2 in, Bulb Housing Glass/Metal, Bulb Shape ED28, Color Rendering Index 65, Color Temperature 4100K, Lumens 38, 000 lm, Light Technology Metal Halide, Overall Length 8 3/8 in, Shatter-Resistant No, Voltage Not Applicable, Watts 400 W, Bulb Beam Angle Not Applicable, Bulb Finish Clear, Rated Life 20, 000 hr, ANSI Code M135/M155, Dimmable No, For Enclosed Fixtures Yes, Bulb Operating Position Horizontal +/-15 Degrees