This pipe tap comes with straight flute style and plug type. It is made of high speed steel material, bright finish, number of flutes are 4, size 1/4", pitch 20, plug 4P-4.5P, pitch diameter limits H3, shank diameter 0.255", tolerance 3B, ANSI standards. Heavy-duty left-hand HSS hand taps are recommended for tapping left-hand threads in general machine or CNC tapping applications. Ideal are for use with steel, stainless steel, and nonferrous metals.