Features: Window door alarm is compact and easy to install, and the double sided adhesive provided is easy to install on windows and doors. Simply attach the main fittings to the door and door frame, or to both windows, and align (leaving a gap of about 10 mm). Once a thief breaks into a door or window and attempts to steal (main and auxiliary separation), burglar alarm can sound a 90 decibel alarm to scare the thief and alert the owner and people around to catch the thief. Specifications: Material: plastic Color: white Power source: battery powered Size: as shown Package includes: 16 x Door and window alarms Notes: Manual measurement, please allow slight errors on size. The color may exist a slight difference due to different screen displays. Batteries are not included.