Used to make new threads or re-thread damaged and/or jammed threads. Also called reverse thread taps. Hand Taps are the most versatile taps for hand use, or for tapping under power. They are popular for use in general machine tapping or CNC tapping and appropriate for tapping the vast majority of materials in through or blind holed conditions. Hand Taps come in three styles Taper, Plug or Bottom.. 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.