Ridgid 35815 Model E-5112 is a 1/8" Hand use pipe tap. This pipe tap is made from carbon steel in right-hand configuration only. This tap is especially suited for restricted area workand has a taper of 3/4-Inch per foot. This tap has a drill size of 21/64 and the nominal pipe size is 1/8-Inch and the threads per inch is 27. NPT.