Door/Window Entry Alarm

It can also be used to alert you of an opening of a sliding glass door, door, window, locker, Gun cabinet almost anything!
Easily mounted by adhesive tape to window or door.
Magnetic sensor switch detects entry protecting your home or office whether you are in or out
Warning door, window sticker is supplied free in package. Operated by 3pcs.1.5VLR44 button cell
Batteries included in the package.