Note-Nuts and washers, including specially designed, are to be classified in this FSC. a. Nuts are a small metal block made in a variety of shapes such as square and hexagonal which is drilled and internally threaded. b. Washers are a perforated piece of metal, leather, or other materials of various shapes or forms. They are used primarily as a seat for a bolt, nut, screw, rivet or nail to distribute pressure and prevent endwise motion over an area and/or to prevent movement between two parts by means of restraining features created by the shape of its edges.

Includes Locknuts; Eye Nuts; Plain Nuts; Castellated Nuts; Wing Nuts; Plate Nuts; Push on Nuts; Concave and Convex Washers; Flat Washers; Keyed Washers; Lock Washers; Shouldered Washers; Split Washers.

Excludes Bearing Thrust Washers (FSC 3120); Shims (FSC 5365); Ring Spacers (FSC 5365); Plate Spacers (FSC 5365); Lock Rings (FSC 5365).