Detects motion within 30 feet. The sensor has a 90 Degree field of vision, giving you a full range of coverage when placed in a corner. The sensor is shaped to stand on a shelf, adhere to a wall, or fit in a corner for maximum room coverage. Set the sensor to be active only in away Mode (so that you wont trigger It when youre at home) or both home and away modes (for rooms that you want covered with a motion sensor while youre home).