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 
Canada 
Italy 
Turkey Classification: Gaskets, washers and other seals, of vulcanized rubber other than hard rubber
NSN 5996-01-437-8824
NSN 6130-01-412-1320
NSN 5975-01-408-6643
NSN 5998-01-037-9366
NSN 2925-01-381-5307
NSN 5960-00-661-0477
NSN 5915-01-316-0429
NSN 6685-00-115-8898
NSN 6650-01-373-4159
NSN 5996-00-323-1294
NSN 2925-00-684-7708
NSN 6645-01-541-5696