Narrow beam indoor motion detector. Protects windows, doors, and valuables. With the MotionProtect Curtain detectors, you can secure the perimeter of your house and freely move indoors. If a stranger breaks in, the system will raise an alarm and call the security company. - Detects motion with a range of up to 15 meters - Works up to 3 years on the pre-installed battery - Transmits alarms at a distance of up to 1,700 meters away from the hub