Lightweight industrial design with multiple hanging points including vertical from the end, vertical from the side and horizontal. Advanced wide T5 optical design for maximum coverage and diffusion. Pre-wired with either 120 or 240 volt 8 ft power cord for ease of use. Highly reflective aluminum insert for maximum performance. Cool operation housing design to keep electrical components thermally stable. Includes Spectralux? 54 watt T5 HO 6500?K Blue lamps. High lumen per watt rating at 5,000 lumens per lamp. Energy efficient electronic T5 ballast. The 8 lamp fixtures have dual on/off switches each operating four lamps. The 4 lamp fixture has an on/off switch that controls all four lamps. US Patent: D757,327 and US Patent Pending: 29/561,608. Chinese Patent: ZL201530031833X. One year warranty on lamps.