Stainless Steel 304/304L Pipe Fitting, Close Nipple, Schedule 40 Seamless, 1" NPT Male, 1-1/2" Length Nipple for connecting and extending pipes Male National Pipe Taper (NPT) threads for connecting female threaded pipes Made of seamless stainless steel 304L for strength Low carbon content to ensure greater resistance to corrosion Meets specifications ASTM A733, ANSI B1.20.1, and ASTM A312/SA312 for quality assurance