Wireless Motion Alert from Chamberlain alerts you the moment someone enters your property. With Chamberlain's Motion Alert you'll always have advance notice that someone's on their way to your door. Compact discreet motion-sensor unit installs on garage mailbox fencepost... nearly anywhere. And when activated it sends a wireless signal to the receiver unit up to one-half mile away! Then when the unit's adjustable chime tells you you're about to have a visitor you can prepare accordingly. Installs in minutes; Completely wireless; Receiver unit accepts signal from up to 4 sensors (one included) so you can protect a whole perimeter.; Weatherproof components.; Sensor: 3 1/4 x 5 1/4 x 3"h. uses 4 AA batteries (not included).; Receiver: 3 1/2 x 3 x 1 3/4"h. uses 4 AA batteries (not included). 1 lb. 11 ozs. Additional Sensors sold below.; Act Now! Chamberlain Wireless Motion Alert / Sensor Kit
- Alerts with light & sound when vehicles or pedestrians are approaching
- 1/2 mile range from sensor to base unit
- Easy installation / easy operation
- Weatherproof outdoor sensor with adjustable sensitivity control
- Expandable up to 4 sensors