Philips 319855 - H37KB-250 Mercury Vapor Light Bulb 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 Philips ED28 bulb, 250W, Base: E39 Mogul Screw, Rated Life (hours): 15000, Color Temp: 5800K, Luminous Flux (LM): 11500