Apollo Horticulture GLBMH600 600 &ndash; Watt Metal Halide MH Grow Light Bulb Lamp E39 Base 600watt Apollo Brand MH bulb compatible with electronic and magnetic ballasts (68,000 Lumens) Metal Halide Light Spectrum Stimulates Vegetative Growth Color Temp: 4200 Kelvin, Engineered for plant vegetative growth Expected Bulb Life: 10,000 Hours Improved Lamp Life and Lumen Output, 110V power voltage Startup Time: 10secs allow 3-5mins for full Warm up. Please wait at least 5mins after power shut off before striking again