The handle/thumb bar is fitted to one side of the door and allows the user to depress the thumblatch. The thumb piece (or thumb bar) passes through the door and lifts the latch bar off the keep. The latch bar is the horizontal bar which is fitted to the other side of the door and is loosely screw fixed at one end to allow upward movement of the thumb bar. This means the latch bar can be lifted off the keep from either side of the door.
Staple pins and/or screw-on-staples are used to restrict the movement of the horizontal latch bar. Either can be used for this purpose.
The frame keep pin is driven into the door frame and screw fixed for safety and used to hold the door/thumblatch closed.