Stainless Steel 316 Cast Pipe Fitting, Coupling, Class 150, 1/2"NPT Female Coupling for connecting and extending pipes going in the same direction Female National Pipe Taper (NPT) threads for connecting male pipes Made from stainless steel 316 for strength Higher corrosion resistance than stainless steel 304 Class 150 fittings conform to standards ANSI B1.20.1 and ISO 49 for quality assurance