Stop intruders! These Bell + Howell® Wireless Alarms fit on doors, screen doors, windows and cabinets, and send a loud warning when they are opened. Or just flip a switch and hear a pleasant chime instead! Installs in seconds without tools. Just peel and stick each self-adhesive alarm where you want it. These Bell + Howell® Wireless Alarms protect your home for thousands of dollars less than security systems. FREE batteries included. Set of 4.