Merit Brass Red Brass Pipe Fitting, Nipple, Schedule 40 Seamless, 1/2" National Pipe Taper Thread Male (Pack of 25) Nipple for connecting and extending pipes Male National Pipe Taper (NPT) threads for connecting female threaded pipes Made from brass for higher corrosion resistance than steel Made of Alloy 230 from seamless red brass pipe for greater ease in machining than yellow brass Meets NSF/ANSI 61 for use in drinking water supplies of pH 6.5 and higher