They are recommended for use in through or blind holes which allow for chip accumulation in the bottom of the hole.
HSS, Spiral Pointed, Tin-Coated, Size: 2-56, Limit H2, Number of Flutes 2 The Machine Tap shoots chips ahead of the cutting action, thus reducing loading and clogging in the flutes. Ideal for threading a wide variety of ductile materials, copper and copper alloys, brass and non-metallics. 2-56 HSS Tin Coated 2 Flute Spiral Pointed Tap Spiral-Pointed taps, or Machine Taps, were originated to solve the problem of tap breakage in through hole tapping.