Specification: Length: 16CM Height: 45MM Width: 45MM Security Door Stop Alarm Are you looking for a cheap and easy way to secure a room? Instead of buying an expensive and complicated alarm system, our battery operated door stop can trigger a 110 decibel alarm and prevent someone from entering. When placed under a door, if the door is opened it will press a pressure plate that activates the alarm. The abrasive rubber base can prevent the door from being fully opened. It's ideal for travelling, student digs, hostels or hotels, and thanks to the light portable design it can be taken anywhere. The best part is when it's turned off it can be used as a regular door stop. Requires a 9V battery (not included).