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 5930-00-144-4994
NSN 5975-01-548-8109
NSN 6110-01-226-7610
NSN 6650-00-515-6002
NSN 6240-01-222-3523
NSN 6610-01-100-3662
NSN 6130-01-435-1879
NSN 5910-01-565-8034
NSN 6130-00-079-1269
NSN 6105-01-554-5023
NSN 5945-00-892-1116
NSN 6645-00-573-7591