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 
Canada 
Italy 
Turkey Classification: Gaskets, washers and other seals, of vulcanized rubber other than hard rubber
NSN 6645-01-062-0905
NSN 5835-00-233-6327
NSN 5935-01-085-5994
NSN 5996-00-299-1609
NSN 6220-00-397-3335
NSN 5996-01-058-3156
NSN 5905-01-032-1109
NSN 6620-01-401-5356
NSN 5925-00-114-2253
NSN 6610-01-091-2908
NSN 6105-01-563-1319
NSN 6685-01-349-3320