The 4-Light (lamps included) T5 High Output Fluorescent High Bay from Lithonia Lighting is an energy-efficient alternative to common HID metal halide high bays. Perfect for manufacturing facilities, warehouses and other commercial applications with ceilings 15 ft. to 40 ft. high. Suitable for suspension by chain, cable or monopolist (sold separately) and operates effectively in ambient temperatures down to -20?F. Consider upgrading to fluorescent high bays to save money on energy and maintenance costs.