The wedge shaped design is made to fit for hinged doors. When the door is opened it compresses the door stop triggering the 118 dB alarm. The trigger has three levels of sensitivity (High, Medium, Low). Special design can be used as a door stop when the power is off. No need to wire your house with high tech security systems you probably don't even know how to use. Simply install the 9V battery and place in front of the door you want secured. Excellent for use when traveling (hotel, motels, etc..).
Very Loud 118db
3 Level Sensitivity Adjustment - High, Medium, Low
Uses 9V Battery