Sun System 1 heat sync aluminum Premium remote ballast with 20.5"x20.75" Sun Grow Horizontal reflector lined with a 95% reflective aluminum insert for high luminescence and louvered on one end and top. Reflector features Adjust-A-Socket mechanism to center any length lamp, accomadates all HID lamp sizes including BT56. Optional tempered glass lens available for UL listing, and air-cool hose fittings. 5-year rebuild or replace warranty.