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 5835-00-111-3419
NSN 6145-01-381-0311
NSN 5920-01-361-8620
NSN 5905-00-481-9239
NSN 5910-00-286-4416
NSN 6320-00-089-9426
NSN 6220-01-212-4088
NSN 6145-00-191-3903
NSN 6645-01-399-0661
NSN 5920-00-066-2699
NSN 5920-01-355-2939
NSN 5985-01-615-1476