Very easy to use and the alarm is EXTREMELY LOUD  you can adjust the sensitivity to the alarm from high, medium to low. IF on low setting, the alarm will go off when a door is opened and fully over the door stopper. If on High setting, the alarm will go off if the slightest thing touches the door stopper. If used on carpet, the door stopper can withhold the force of a grown man pushing on the door.

Dual Function: Can be used as a door stop alarm and door stopper, Its high damping rubber bearing can prevent the door sliding and prevent the bad guys into. A protector around you. Can be used in home and travel. Notice: The door stop alarms fit for the gap between the door and the ground be 0.6'' and 1.2''.

3 Level of Sensitivities: High-Medium-Low Sensitivities, which can be adjusted according to your own needs.

Loud Alarm: Very loud shrill that would definitely scare someone away with 120db alarm. Weight: 4.5 oz.

Powered by 9V Battery: The door stop alarm powered by 9V battery, One piece can be used for a year under normal circumstances. Very practical.

Easy to Use: No installation required, Simply place the alarm behind any inner pull door (home, hotel, etc). very convenient to take with you when travel or stay indoor alone. A really must have around you.