The door stopper alarm is in "on" status, when door pressure is applied, the door alarm will be triggered while make extremely loud 120db alarm, helps wake/alert homeowner or renter, helps deter intruder and possibly notifies neighbours, security protection.

When door stopper alarm is in the "off" state, it acts as common door wedge, its high damping rubber prevents the door from sliding and keeps the door in the open position.

3 Sensitivity Levels – Low - Medium - High, with an adjustable sensitivity switch on the side; H level is the most sensitive level that vibration will trigger an alarm; please note when the alarm sound gradually becomes smaller, it means to replace the new battery.

No wiring needed, just put 1x9V battery ( not included) in , place it under the door, the gap between the bottom of the door and the floor should be 10mm(0.38 in) to 35mm(1.35 in)and switch the button on the back to “ON” then it can works.

The package includes 2 door alarms, each weight about 120g; easy to carry; alarm loud 120db to protect you; great for travel, apartment, home, etc; to protect you when traveling or working alone. A protector who really must be around you.