Aeon Labs Aeotec DSC 17103 - ZWUS Micro Double Switch 2-Relay Switch - Controls 2 lights Small Size for Easy Invisible Installation Reports Energy Usage Built-in Signal Repeater The wireless module is powered from the mains supply and is a three-wire design which requires a neutral connection. In the event of power failure, non-volatile memory retains all programmed information relating to the units operating status By taking advantage of the Z-Wave mesh network, commands can be routed to their destination via intermediary "listening" Z-Wave products. Products that are Z-Wave certified can be used and communicate with other Z-Wave certified devices.