See Hinge.

Type of hinge on eyeglass frames that is more flexible than a regular hinge, making the frames more durable.

A hinge with a coil spring in the center that returns door to a closed position.

A hinge with flanges or leaves which attach to the door and jamb and are connected to the hinge pivot point(s) (barrel). Springs provide energy to close a door from the open position or, in some cases, open a door from the closed position. Single acting spring hinges are often listed for use on fire doors.

A hinge containing one or more springs to move the door into the desired position. It may be either single or double acting.