The Radiant is designed to deliver the brightest possible light down to your plants. The patented double-wall design and generous reflective cavity make it the coolest running fixture on the market. Constructed of heavy duty pre-galvanized steel and lined with high purity European aluminum, the Radiant will give years of dependable growing performance. Directs light downward for maximum light intensity and growth Cool running patented double-wall design allows placement of light closer to plant Multi-faceted computer-designed aluminum interior for maximum efficiency Instructions, hangers, and lighting recommendations included. UL Listed Reflector Size: 9-3/8"H x 21"W x 21"L Accepts: Sodium 400, 430, 600, 1000 - Halide 400, 1000