Easy and fast sensor The infrared sensor detects movement and sends a signal to the receiver. Choose from 38 ringtones with bright LED light. Wireless Plug-in ReceiverPortable plug-in receiver plugs into any standard outlet. The sensor uses 3 AAA batteries (not included). The detection delay between motion sensor alerts is configurable from 30 seconds. Simply place the sensor at the entrance to your driveway and the receiver inside your home. Extensive Working RangesWork tables up to 230 feet (70 meters) between the receiver and the transmitter allowing you to place it a safe distance from the receiver to alert you to the arrival and departure of family members, unsolicited attorneys or solicitors, or anyone visiting your home or business br>Widely UsedIdeal for front doors, window frames, driveways, walkways and anywhere around the house you want to be alerted. Also great for alerting business owners who work behind or out of sight, to customers entering their store. Wireless InstallationSensor is wall mountable, don't worry for installing the problem.