Securing rooms from unauthorized entry couldn't be easier. The Door Stop Alarm requires no wires or complicated installation and is powered by a single nine-volt battery (not included). Simply place the pressure-sensitive door stop alarm at the base of any door, and the device will emit a powerful 120-decibel alarm when the door is opened. The Security Door Stop Alarm is extremely compact, so it's convenient enough to take anywhere. With this handy gadget, you'll be able to secure your hotel room, dorm room, apartment or any room in your home.