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 6320-01-265-0665
NSN 6685-01-655-9241
NSN 6130-00-817-7899
NSN 5965-01-146-9162
NSN 6110-00-941-8347
NSN 5990-00-765-1264
NSN 6110-00-983-5927
NSN 5905-00-932-4240
NSN 5950-00-522-2432
NSN 5905-01-167-3278
NSN 5998-01-385-2926
NSN 6220-01-492-3789