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 
Greece Classification: Gaskets, washers and other seals, of vulcanized rubber other than hard rubber
NSN 6110-01-301-7382
NSN 6150-00-661-0184
NSN 5965-01-254-3622
NSN 6240-01-124-1049
NSN 5999-01-358-0403
NSN 5996-01-162-4969
NSN 5998-01-128-2351
NSN 6220-01-538-7194
NSN 6620-01-116-3983
NSN 6135-00-170-8819
NSN 5855-00-149-0766
NSN 5920-01-372-1322