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 5895-01-571-8577
NSN 6645-00-947-0625
NSN 6620-01-026-1776
NSN 4140-01-295-4287
NSN 5960-01-278-9394
NSN 5835-00-670-2925
NSN 6135-00-635-9187
NSN 5920-01-122-1509
NSN 6620-01-036-0751
NSN 5960-01-252-4153
NSN 5920-01-192-3798
NSN 6650-01-586-7061