3/4-14 HIGH SPEED STEEL, NPT PIPE TAP. 5-FLUTES. GENERAL PUPPOSE PIPE TAPS ARE APPROPRIATE FOR THREADING A WIDE VARIETY OF MATERIALS BOTH FERROUS AND NON-FERROUS. THE NOMINAL SIZE OF A PIPE TAP IS THAT OF THE PIPE FITTING TO BE TAPPED, NOT THE ACTUAL SIZE OF THE TAP. THE THREAD TAPERS 3/4 OF AN INCH PER FOOT. ALL PIPE TAPS FURNISHED WITH A 2-1/2 TO 3-1/2 THREAD CHAMPHER. NPT THREADS REQUIRE THE USE OF A SEALER LIKE TEFLON TAPE OR PIPE COMPOUND.