No longer at the mercy of the weather. The iPower 600-watt Metal Halide Bulb lets you grow better by providing reliability and performance. By concentrating its output around 450-500nm (blue to white) wavelength of light, this bulb provides the essential spectrum needed for most plants on maximizing short internodes and chlorophyll density. * Weight 0.375-pound * Maximum power 600-watt * Base type Mogul E39 * Initial lumen (Lm) 55,000 * Color temperature (K) 6,500 * Color index (RA) 65 * Expected Life Span (Hr) 15,000 * Frequency (Hz) 60 * Bulb orientation vertical and horizontal * Non insect-luring * Good fog penetration * Compatible with all standard 600-watt digital ballasts