The medium- and long-throw high-intensity M2901 Series is designed for a 100W PAR38 ceramic metal halide lamp. The extruded aluminum housing has an integral thermally protected electronic ballast. There is a self-locking feature for both horizontal and vertical focusing, and the capacity for accessories: color filters, spread lenses, louvers, light-blocking screens, and UV-blocking filters. Available in five finishes, it measures 6 5/16 inches high by 10 inches wide.