Plug Vs. Bottoming Taps: Choosing The Right Tap For Your Application

Plug taps, designed to create blind holes, feature a full-length thread that cuts all the way through the workpiece. Bottoming taps, on the other hand, are intended for through holes and have a partial thread, extending only partway up the shank. They cut threads only in the bottom portion of the hole, leaving the upper section unthreaded for bolt clearance.