The Merit Brass square head solid plug is a class 150 stainless steel 304 cast pipe fitting with male National Pipe Taper (NPT) threads for closing the end of a pipe. The plug inserts into female pipes or fittings and connects with NPT threads, which create a tighter seal than straight threads, and it has a square head for increased leverage and use with a wrench during installation and disassembly. Made of stainless steel 304, the low carbon content of this plug 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.

Pipe fittings are components used for connecting, terminating, controlling flow, and changing the direction of piping in many different industries. When purchasing pipe fittings, consider the application, as this will affect material type, shape, size and required durability. Fittings are available threaded or unthreaded, in many shapes, styles, sizes, and schedules (pipe wall thickness).

Merit Brass manufactures pipe nipples following ISO 9001 standards for quality assurance. The company, family-owned since 1937 and headquartered in Cleveland, OH, distributes pipe fittings in the United States and Canada.