Carbon Steel * Hand Tap Set includes Taper Plug and Bottoming Taps * 5/8-11 * Number of Flutes 4 * Carbon Steel Hand Taps are used to re-thread damaged and/or jammed threads. Carbon Steel Hand Taps may also be used to thread mild steels. Taper Style: Starts the thread square with the workpiece. Plug Style: Generally used in thru holes. Bottom Style: Generate the thread to the bottom of the hole.