Stainless Steel 316 Pipe Fitting, Cap, Class 1000, 1" NPT Female Cap for closing the end of a pipe Female National Pipe Taper (NPT) threads for closing male threaded pipes Made from stainless steel 316 for strength Higher corrosion resistance than stainless steel 304 Conforms to specifications ASTM A182, ASME SA182, and ANSI B16.11 for quality assurance