Safety Technology International, Inc. STI-WS102  Burglar Stopper Door/Window Sensor Protects access points around the home including those on or in garages, cabinets, sheds, attics, side doors and freezers Alerts when protected door/window or other monitored portal is opened Protect access points around the home or office Magnetic sensor mounts on either right or left side of door or window Backup battery and low battery notification