Champion Cutting Tool 302 series carbon steel hand tap 3 piece sets come matched with a taper, bottom and plug tap. For hand tapping in maintenance and repair work. As well as re-threading applications where extreme thread accuracy and tolerance is not critical. These carbon taps will create new threads and clean up damaged threads. Taper taps distribute the cutting load across 7-10 threads. Used for starting a threaded hole. Plug taps are most commonly used, distributing the load across 3-5 threads of champer. Bottoming taps have only 1 to 1-1/2 threads of chamfer and are used to tap to the bottom of a blind hole. Operated in hand tapping wrenches or production tapping heads for general purpose tapping.