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 6650-01-116-9731
NSN 6240-01-260-3597
NSN 6105-00-986-8231
NSN 6645-00-163-0821
NSN 5950-01-075-7275
NSN 5895-01-426-8942
NSN 5975-00-132-2911
NSN 5996-01-048-5196
NSN 5945-01-366-3123
NSN 7035-01-462-0516
NSN 5960-01-325-2241
NSN 5915-00-454-5901