Skylink SW-18 Wireless Outlet Control Switch with Rolling Code Technology Skylink Rolling Code Technology. Easy to install, no special tools required. Turn on/off lights, fan, and small appliances with a simple push of a button. Keychain style transmitter (long-life alkaline battery included) that goes with you. Compact-size dual button transmitter can be used to control another SW-18R Wireless Switch Receiver FCC/IC approved. UL listed. One year warranty.