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 6150-00-383-7883
NSN 5905-00-649-0425
NSN 5925-01-463-6888
NSN 6220-01-450-4659
NSN 6150-00-824-0075
NSN 5920-01-041-5378
NSN 5905-01-576-8394
NSN 6645-01-367-8911
NSN 6320-00-382-7825
NSN 6130-01-634-0603
NSN 5999-00-831-6098
NSN 6110-01-252-6689