WIRELESS ENTRANCE ALERT DescriptionWireless Entrance Alert Sounds a chime when a monitored door is opened The Receiver plugs into any standard household AC wall outlet and can be up to 150 feet away from the door Transmitter uses one 6 volt alkaline battery (included) Wireless Entrance Alert Sounds a chime when a monitored door is opened The Receiver plugs into any standard household AC wall outlet and can be up to 150 feet away from the door Transmitter uses one 6 volt alkaline battery (included)