LOUD AND BIG ALARM: Door and window sensors powerful enough to detect intruders, prevent children and babies from leaving the house, and protect your office, garage, dorm room, or apartment both indoors and outdoors. You can certainly hear it from another room and be noticed. Don't worry if small children play with it. Simply place it high up where they can't reach it. Works on sliding doors, windows, drawers, and refrigerators. Prevent children and babies from leaving the house without warning. Protect your home from burglars who enter and exit through windows and doors. EASY INSTALLATION: Clean the flat surface, peel off the sticker, mount the alarm on the door, and the magnetic strip on the doorpost. Done! Easy to install with the sticker. Simply touch the window or door. Ideal entrance sign for houses, apartments, RVs, offices, hotel rooms, garages, etc. Note: The data is measured manually. Please allow 1-3 cm deviation. Due to different lighting conditions and displays, color