Anvil 2122 Forged Steel High Pressure Pipe Fitting, Class 6000, Square Head Plug, 1/2" NPT Male, Galvanized Finish Square head plug for closing the end of a pipe or fitting Male National Pipe Taper (NPT) threads for connecting to a female threaded pipe Forged steel for weldability, rust resistance, and durability with a galvanized finish for a protective coating Class 6000 fitting for use in high-pressure applications Meets specifications ASTM A105 and ASME/ANSI B16.11 for quality assurance