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 6105-01-476-1671
NSN 5990-00-226-1152
NSN 5996-00-220-3322
NSN 5985-01-646-5761
NSN 5915-01-236-8364
NSN 6130-01-342-2469
NSN 5935-01-063-7125
NSN 5965-00-238-3721
NSN 5960-01-097-0083
NSN 6145-01-412-6087
NSN 5985-01-634-0635
NSN 5925-01-139-3866