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 5920-00-467-1933
NSN 7035-00-142-9076
NSN 5930-01-606-2299
NSN 5996-01-496-3180
NSN 6145-00-294-0830
NSN 5935-01-265-0333
NSN 6685-00-478-1858
NSN 6645-01-017-8576
NSN 5855-00-320-4116
NSN 6685-01-415-3117
NSN 6145-01-545-4784
NSN 6130-01-599-3926