Motion sensor alarm alerts you the moment someone enters your property.With this system， you'll always have advanced notice that someone's on their way to your door.Compact， discreet motion-sensor unit installs on garage， mailbox， fencepost... nearly anywhere.And when triggered， it sends a wireless signal to the receiver unit， up to 400 feet away!Installs in minutes， no tools needed，completely wireless.Sensor is extremely weather resistant.Wall mountable，low consumption.Receiver: plug-in 220V UK，EU style plug or Plug-in 110V American style plug available.Sensor: 4.5V 3xAAA battery (not included).Material: ABS.Working mode:alarm， chime.Control distance: 400ft.in open air.Please remark the plug you need on order detail，otherwise I will send the plug according to your country electricity supply condition