LOUD DOOR : This alarm is loud enough to immediately sound a strong alarm when someone illegally opens a door or window, high-quality magnetic sensors trigger alarms up to 90dB, protects your home and place, prevents children from out of the room and lost, super durability and stability. PORTABLE: Ultra-thin design, 3.4x1.1x0.6inch, and easy to carry, to protect your important items. Perfect entry warning for homes, apartments, mobile homes, offices, hotel rooms, garages, and more. EASY INSTALLATION: Simple paste installation and operation, press the on/off switch to turn the power on/off, insert 2 AAA batteries (batteries are not included), peel off the double-sided tape and paste it on the door, the distance between the magnet and the alarm should not exceed 0.6in. MULTIPLE SCENARIO USE: Wireless sensor door window burglar alarm can be used in homes, apartments, mobile homes, hotel rooms, offices etc.., Weight: 0.33730726086 Pounds, Manufacturer: NONDK