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 6645-00-274-5670
NSN 5999-01-389-8252
NSN 5910-01-483-3029
NSN 5920-01-364-7706
NSN 5985-01-472-3360
NSN 5895-01-344-6136
NSN 5835-00-690-8898
NSN 5855-01-172-4568
NSN 4140-01-240-3300
NSN 6145-00-296-0085
NSN 5895-00-296-9708
NSN 5985-00-684-6847