GE 27501 - 320 Watt - ED28 - Multi-Vapor - Pulse Start - Metal Halide - Protected Arc Tube - 4000K - Mogul Base - ANSI M132 or M154 - Vertical Base Up Burn - MVR320/VBU/HO/PA HID Bulbs produce high output for their size making them a compact powerful &amp; efficient light source HID Bulbs are used for general lighting, professional lighting fixtures, growing applications HID bulbs put out around 3-5 times greater output (lumens per watt) than traditional halogen bulbs GE ED28 bulb, 320W, Base: E39 Mogul Screw, Rated Life (hours): 20000, Color Temp: 4000K, Luminous Flux (LM):