OptioTM OPT41000HP/OPT41000HP15 Dimmer Modules contain four high-performance IGBT dimmers. IGBT Dimming technology provides quiet lamps, quiet dimming modules without buzzing, long lamp life, higher energy efficiency, less waste heat, and short circuit immunity. Each dimmer employs solid-state Insulated Gate Bipolar Transistor (IGBT) devices which are rated at no less than six times the dimmer's rated capacity. They are c.U.L. recognized and rated for operation at 120VAC, with a capacity of 1000 watts per dimmer. The module is ruggedly designed, fully enclosed module. Modules are easily installed into an OptioTM Lighting Control Panel, and may be easily interchanged with other OptioTM modules.