Security Door Window Entry Burglar Alarm System with Magnetic Sensor. Features a new and high-quality design with a super loud 120 dB alarm. Easy installation—simply peel and stick. Offers excellent environmental suitability and stability, providing dustproof and insect prevention protection. Easily mounted using adhesive tape. Suitable for windows or doors. Ideal as an entry warning device for homes, apartments, mobile homes, dorms, offices, hotel rooms, garages, and more. The magnetic sensor switch detects unauthorized entry to help protect your home or office whether you are present or away. Includes a warning door/window sticker. Operated by 2 AAA batteries (not included). Specifications: Sensor Type: Alarm Alarm Type: Sound Material: Plastic Size: 3.6 x 1.2 x 0.7 inches Package Contents: 10 x Alarm Unit 10 x Magnetic Sensor