TechInfo: Just plug each unit into a standard 230 V ~ 50 Hz outlet, and it will work! Mains or battery powered receiver - no need for extra socket!Pack Details: 1 Transmitter: converts IR signals of remote controls into 433.92 MHz RF messages and transmits them to the Receiver, even through walls and ceilings. 1 Receiver: converts RF messages back into IR signals to control the selected A/V source. 1 remote UR81