NRG LightMaster 2000 Transmitter Command Module.

The Lightmaster 2000 is a wireless command system that allows you total control over any number of AC lights from up to 150 feet away, even through walls. Never again trek across a crowded dance floor, disrupt a news conference, or spend time taping down cables. Simply plug any AC light (up to 1,000 watts) into a control module and you're in total control using a tiny hand-held radio-frequency transmitter. Since you can add an unlimited number of control modules, the Lightmaster can be expanded as your lighting needs grow. Lightmaster modules can be easily set to a unique address to avoid interaction in crowded environments where other Lightmasters may be in use.