1/2"-28 Size Plug Tap. 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. 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. Tap sets come with three taps, one of each: Taper, Plug and Bottoming tap.