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 5996-00-553-7348
NSN 6610-01-108-7273
NSN 6240-01-058-8868
NSN 7035-01-391-7470
NSN 2925-01-633-4048
NSN 5895-00-246-4415
NSN 5998-01-360-8283
NSN 5950-00-753-0955
NSN 5996-01-203-1938
NSN 5895-01-346-2624
NSN 5960-01-187-3103
NSN 6650-01-297-3370