The Merit Brass hex locknut is a class 150 stainless steel 316 cast pipe fitting with female National Pipe Taper (NPT) threads for locking two fittings into place for stability and reduced vibrations. The locknut has NPT threads for creating tighter seals than straight threads. The hexagonal shape provides increased leverage for use with a wrench during installation and disassembly. This locknut is made of stainless steel 316, which is higher strength and more corrosion resistant than stainless steel 304. The class 150 fitting meets standards ANSI B1.20.1 and ISO 49 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. Family-owned since 1937, the company is based in Cleveland, OH. Merit Brass distributes pipe fittings to the United States and Canada.