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 5998-01-613-0661
NSN 5965-01-601-0725
NSN 6610-01-265-1824
NSN 5930-00-620-4173
NSN 6150-01-299-9133
NSN 6240-00-011-5273
NSN 5895-01-211-4156
NSN 6105-00-878-9445
NSN 6685-01-432-2090
NSN 5950-00-243-3076
NSN 4140-01-262-9164
NSN 5915-00-681-7674