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 5935-01-449-1852
NSN 5990-01-025-7466
NSN 7035-00-153-3826
NSN 6610-01-420-7817
NSN 7035-01-633-9537
NSN 6685-00-186-9190
NSN 5999-00-842-0824
NSN 5999-01-521-8713
NSN 5910-01-304-2021
NSN 6220-00-144-8043
NSN 6110-01-470-2688
NSN 6650-00-464-6395