Each high-carbon-steel tap and die in this 40-piece Vermont American Metric Tap and Die Set has size and starting side permanently marked on each. All taps are plug style and have the recommended ...

Thus, a tap or die marked 1/4-20 NC cuts threads for a 1/4-inch-diameter screw or bolt with 20 coarse threads per inch. Taps and dies with diameters less than 1/4-inch are numbered according to ...