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 5990-01-579-2711
NSN 6135-00-128-1633
NSN 5935-01-415-4468
NSN 5920-01-643-3997
NSN 6105-01-463-2387
NSN 6220-01-207-1229
NSN 6650-01-531-9827
NSN 5915-00-540-8350
NSN 5905-01-534-7894
NSN 5945-01-064-6186
NSN 6685-01-160-6938
NSN 6645-00-124-9939