This tool kit offers a three-step tapping procedure (taper/start, middle and bottom). For use in automotive and repair work, general workshops and machine repairs. 3-step threading procedure (taper/start, middle and bottom). For use in automotive and repair work, general workshops and machine repairs. Contents: A tap and die set usually consists of the tap and the die. The stud is designed for internal threading and is therefore used on the fastener hole or a nut, while a die is used for external threading, as on a bolt