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 6320-01-544-2799
NSN 5999-00-966-5137
NSN 4140-01-061-5629
NSN 6645-01-376-2336
NSN 6620-00-470-0879
NSN 5935-00-887-7082
NSN 5835-01-111-9838
NSN 5950-01-412-6515
NSN 5930-01-125-9165
NSN 5905-00-397-8477
NSN 5998-01-264-8846
NSN 2925-00-225-5386