DESC: Protects an area up to 35 ft. long by 84 degrees wide. Picks up movement in the protected area and immediately signals the control panel. Easily installed on wall or in corner of room with supplied mounting bracket. Battery saving "idle" feature provides 2 minute delay between each transmission. Low battery indicator light and warning signal transmitted to the control panel. Compatible with all Home Sentinel Wireless Security Systems. 9v battery includedThis product is quality reconditioned by the manufacturer