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 5935-01-200-2827
NSN 5996-00-799-8838
NSN 2925-01-027-1293
NSN 6135-01-481-5109
NSN 5960-01-522-0391
NSN 5930-01-275-8315
NSN 5965-01-160-7037
NSN 6645-01-369-4371
NSN 2925-01-435-9057
NSN 5835-01-167-1824
NSN 6610-00-732-2488
NSN 6150-01-616-6538