Door Window Alarm 2 Pack Noopel Home Security Sensor Burglar Anti-Theft 120DB Alarm with Batteries Included – DIY Easy to Install (2)

Magnetic door window alarm sensor 120db alerts a person to a door or window opening. Please note: this alarm does not work on uneven surfaces.
Prevent children going out the house without notice. Also ideal entry warning for your home, office, apartment, garage and so on.
Ultra-thin door and window alarm with 2 adjustable settings (off/on).3xLR44 batteries included.
Easy installation, No wiring needed! No screws needed! Included double sided tape! Note: make sure the gap between the alarm and magnet sensor within 0.39inch.
Ultra-sensitive also Low battery indicator to check battery life. This is a PERFECT AFFORDABLE compliment for your home security.