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 7035-00-064-7008
NSN 5996-01-440-9660
NSN 4140-01-265-0731
NSN 2925-00-737-6476
NSN 5930-01-459-2664
NSN 5975-01-350-7682
NSN 6220-01-500-7388
NSN 6130-01-400-6123
NSN 2925-01-197-7864
NSN 6130-01-166-1383
NSN 5910-01-616-3821
NSN 6320-01-384-7079