Drill America DWT Series Carbon Steel hand re-threading tas are used to re-thread damaged and/or jammed threads. Carbon Steel Hand Taps may also be used to thread mild steels. Hand Taps are the most versatile taps for hand use, or for tapping under power. Hand taps are popular for use in general machine tapping or CNC tapping. They are also appropriate for tapping the vast majority of materials in through or blind holed conditions. Carbon steel Hand Taps come in three styles: 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. A tap set contains 1 taper, 1 plug and 1 bottoming tap.