I ordered these alarms in the hopes it would keep someone from entering our home or, at the very least, alert us by making the dogs bark! We also have a young child who visits our home from time to time and a pool, this child can run like the wind so an adult is always nearby, so this alarm would give us a heads up before he even gets the door open. It is loud. I know everyone leaving a review says it is loud, so believe it. They are very loud.