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 6110-01-442-0661
NSN 6320-01-476-7702
NSN 5975-01-558-5817
NSN 5915-00-228-9890
NSN 5965-00-661-0469
NSN 5895-01-044-6369
NSN 5985-01-231-7056
NSN 4140-01-323-4279
NSN 6130-00-156-4550
NSN 6320-01-379-1182
NSN 6150-01-610-2199
NSN 5910-00-227-0848