Never be caught off guard again. Chamberlain® wireless motion alert systems detect motion and alert you when a pedestrian or vehicle approaches your home or property. The weather-resistant motion sensors feature an adjustable sensitivity control to prevent false alarms from small animals. Each system has up to a 1/2 mile range, long battery life, and can be easily installed practically anywhere that demands notification or protection – driveways, garages, sheds, business fronts, or even back entrances. The systems can also be expanded to help protect your property even further.