A washer having a centrally located hole with a solid or laminated cross-section and two flat parallel bearing surfaces. The hole must be 75 percent or less than the largest dimension and the bearing surface finish is greater than 32 microinch (0.8 micrometer). The thickness cannot exceed 25 percent of the largest outside dimension. When the largest outside dimension is less than 1/4 inch or 6mm, the thickness must be 0.006 inches (0.15mm) or greater and for items 1/4 inch (6mm) or larger, the thickness must be 0.016 inches (0.4mm) or greater. The maximum tolerance is applied to dimensions and used as a determining factor. Items with separable lamination use shim. For items fabricated from ceramic or electrically rated materials by specification or industry standards use insulator (1), washer. Excludes disk, valve, graphite impregnated and lubricated items.
Dept. of the Navy 
Italy 
Turkey Classification: Gaskets, washers and other seals, of vulcanized rubber other than hard rubber
NSN 6650-01-212-3964
NSN 5965-00-295-9606
NSN 5935-00-146-4224
NSN 6220-01-619-2512
NSN 5990-01-196-2953
NSN 5935-01-235-4783
NSN 6650-00-113-4102
NSN 5910-01-592-5921
NSN 6645-01-479-5364
NSN 5930-00-210-3021
NSN 4140-01-086-0067
NSN 5910-01-403-2812