The Sturdy Door Stop Alarm has an easy-to-use design and powerful effectiveness, it's your best bet when it comes to keeping intruders away. Simply place it behind the door and turn it on, and should someone attempt to open the door, an alarm will sound at 120 decibels - loud enough to scare off any suspicious visitors. When traveling or away from home or the office, take your Door Stop Alarm with you for extra peace of mind. Wherever you may be, you'll be confident knowing your property is secured by this trusted security device.  Size (inches): Height 1.5" x Length 5" x Width 1.6".