Anvil 8700159901, Malleable Iron Pipe Fitting, Square Head Plug, 3/4" NPT Male, Galvanized Finish Plug for closing and terminating the end of a pipe or fitting Male National Pipe Taper (NPT) threads for connecting to a female pipe or fitting Made from malleable iron for tensile strength NPT threads for creating a tighter seal than straight threads Galvanized finish for corrosion resistance in water, air, and steam applications