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 5960-00-357-3043
NSN 5935-01-495-1125
NSN 6130-01-312-3510
NSN 5998-01-541-1250
NSN 6620-00-246-5159
NSN 6240-01-616-6813
NSN 6110-01-461-2631
NSN 6110-00-715-9404
NSN 5950-01-128-3975
NSN 4140-00-972-9513
NSN 6130-01-035-5584
NSN 5990-01-580-2191