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 Army 
Dept. of the Air Force 
Dept. of the Navy Classification: Copper washers including spring washers not threaded
NSN 6145-01-492-1701
NSN 6105-01-634-0322
NSN 6650-01-447-2858
NSN 5935-01-136-7667
NSN 6240-00-235-5159
NSN 2925-00-679-8131
NSN 5915-01-158-6864
NSN 5935-01-256-9637
NSN 5835-01-580-0446
NSN 6685-01-101-2574
NSN 5950-01-025-1649
NSN 6650-01-553-2805