Simply Automated US11-40-W Custom Series Single Dimming Transceiver, White Standard 900W single-rocker dimmer with white faceplate. Works just like a regular light switch or dimmer. Built-in (countdown) timer option for convenience and energy savings. Utilizes ultra-reliable Universal Powerline Bus (UPB) technology. No new wiring needed! For new or existing lighting fixtures, lamps, fans and other electrical devices. Powerful expansion capability  up to 250 devices using UPStart software, your PC and Computer Interface Module (PN: UMC-USB)! Can transmit and receive scenes with other Simply Automated dimmers, plug-in modules, wall receptacle, fixture modules and other UPB devices  can control virtually any UPB device that connects to AC power wiring anywhere in the home. Dimmers require both a neutral (white) and hot (black) connection. Do not use on a 3-way circuit. Your home should be no more than 2500 square feet and have only one breaker panel. A phase coupler is required in some home installations.