Item dimensions L x W x H 19 x 7 x 3 centimeters Battery description LR44 Number of batteries 3 Product specific - included 120 dB sound level About this item Security System for Your Home - 120 DB Siren alarm can not only cause huge shock to thieves, but also allows you to wake up while sleeping to prevent horrible accident. A door and window alarm with wide applications, forcible entry warning, ideal for home, office, hotel, apartments, garages, dorm room, or even RV. Keep Your Children Safe - This magnetic wireless sensor door and window alarm is powerful enough to detect entry, it lets you know when your children open the doors or windows to prevent children and babies from going out, whether you are inside or outside the house. (audible distance up to 750 ft / 230 m). Especially, if you have a swimming pool at home, it is very necessary to install a door alarm. Smart Design and Easy to Use - Size: 6.4x4.25x1.7cm, door and window alarm with smart size, alarm sound: 120 dB, unique ultra-slim door and window alarm, design with 3 adjustable settings (on / off / set). Magnetic Wireless Sensor Triggered Alarm: Alarm triggered after door entry or window opening. Easy to Install with Double Sided Adhesive Tape - Easily mounted on window or door with tape. No wiring needed! No screws needed! You can install this alarm on all windows and doors, drawers, doors and other flats. When the alarm goes low, you should replace the batteries to better protect your home.