487-20 Merrit Brass T304 1-1/4" Stainless Steel Union The Merit Brass union is a class 150 stainless steel 304 cast pipe fitting with female National Pipe Taper (NPT) threads for connecting and extending two male threaded pipes. The union has three pieces and includes a threaded connection that can be screwed or unscrewed to connect or disconnect pipes more easily than couplings. It has NPT threads on both ends for creating tighter seals than straight threads. Made of stainless steel 304, the lower carbon content of this fitting ensures higher corrosion resistance than 302 grade steel. This class 150 fitting meets standards ISO 49 and ANSI B1.20.1 for quality assurance. Class is a standard relating to tolerance, construction, dimension, and wall thickness, but it is not a direct measurement of maximum working pressure.Union for connecting and extending two male pipesFemale National Pipe Taper (NPT) threads on both ends for connecting two male threaded pipeMade of stainless steel 304 for greater strength than 302 grade steelLow carbon content for greater resistance to corrosionMeets standards ISO 49 and ANSI B1.20.1 for quality assurance