Stainless Steel 304 Cast Pipe Fitting, Cap, MSS SP-114, 1/2" NPT Female Cap for closing the end of a pipe Female National Pipe Taper (NPT) threads for connecting to male pipes Made of stainless steel 304 for greater strength than 302 grade steel Lower carbon content for greater resistance to corrosion Conforms to standards MSS SP-114, ANSI B1.20.1, and ASTM A351 for quality assurance