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