ensure the safety of people and property: alarm volume for the door and the Window sensor reaches 130 decibels, after the door is opened, it will emit a sound, which can not only cause a huge shock to the burglar, but also let you wake up from sleep to avoid horrible accidents. A widely used door and window alarm, perfect for home, office, hotel, apartment, garage, dorm, and even RV. Durable and Long Standby Time: Anti-theft alarm can be used for one year without frequent battery replacement. Batteries (2 AAA batteries for each door alarm and a cr2032 for the remote control not included). These batteries are easy to purchase and replace. An audible alarm will be played. Therefore, when someone illegally opens the door and window (the main unit is separated from the magnetic strip), the siren will immediately emit a high-pitched sound. Easy to install with double-sided tape - double-sided tape included. Easily installs to windows or doors with adhesive tape. No wiring required! No screws required! You can install this alert on All windows, drawers, doors and other panels. "Note: The data is all manually measured, please allow 1-3cm error, due to the difference in light and display, there will be a certain color difference, l actual item received shall prevail.