Exit Device
An exit device is used to unlock a door during an emergency. It is a spring-loaded metal bar attached horizontally to the inside of an outswinging door. When the bar is depressed it activates the mechanism and unlatched the door, allowing the door to be opened. These doors can also be opened from the outside, if a trim piece or key cylinder is added. They may also be dogged open from the inside to allow access from either side.