The door stop alarm will sound if the unit is moved or if the door is opened. You can use this alarm too block a door from being opened. If anyone tries to open the door, the  alarm will sound. There is also a movement sensor with adjustable sensitivity to activate the door stop alarm if tampered with.

Description:
1.Power supply: DC 9V battery
2.Alarm decibel: ¡Ý85db/3m
3.Temperature: -10~+40
4.Humidity: <95%