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 5905-01-066-9337
NSN 5990-01-369-3380
NSN 6110-01-206-4187
NSN 5975-01-158-3009
NSN 6240-01-391-0399
NSN 5895-01-548-6088
NSN 5999-01-158-6922
NSN 5910-00-019-0709
NSN 5895-01-096-8773
NSN 5998-01-656-3920
NSN 6645-01-432-7943
NSN 5925-00-946-9423