Completely sealed featuring hinged glass and double gasket (between glass & reflector and glass & frame) for an air-tight seal. Includes tempered glass, built-in socket and 15 ft lamp cord. Highly reflective aluminum interior for excellent reflectivity and diffusion. Swing Stop® retention cable keeps glass from abruptly swinging down. Captured thumb screws & closure mechanism for ease of use and excellent sealing. Air-cooling flanges have a bead ring to keep ducting securely in place. Powder-coated galvanized steel housing. US Patents: D698,628, D543,652, D613,900.