The 18-8 stainless self-locking serrated hex flange nut has a plain finish and meets American Society for Mechanical Engineers ASME B18.2.2 specifications. The nut has a flanged base on one end that eliminates the need for a washer when fastening components. It has a self-locking serrated flange that digs into the material being fastened to help prevent loosening. The body has a hex shape with six flat sides that a wrench can grip to turn from the side, enabling use when there is no space above the nut. The 18-8 stainless steel material provides strength and offers good corrosion resistance in many environments. The material may be slightly magnetic. Width is measured as width across flats.

Nuts are internally threaded fasteners that are used with bolts and threaded rods and studs to connect components. Several different nut styles fit a variety of application and installation requirements. Some styles, such as hex nuts, acorn nuts, flange hex nuts, and coupling nuts, must be tightened with a tool. Others, such as eye nuts, thumb nuts, and wing nuts, can be tightened by hand. Some nuts have a self-locking mechanism, such as a nylon patch or distorted threads, that makes them suitable for applications with a high amount of vibration.