The screw on this Miniature Wheel/Gear Puller exerts controlled pressure to force tiny wheels, gears and clock hands away from the post without damaging surfaces. This tool is absolutely essential for preparing or modifying model railroad rolling stock, clock repair, slot car motor gear removal, and many other applications. The overall height of the screw and post is 1-3/4", and the post is 7/16" in diameter. The jaw frame is 1" wide and the jaws adjust to a maximum opening of 7/16".