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 
Spain 
Republic of Korea 
Italy 
Greece 
Turkey Classification: Copper washers including spring washers not threaded
NSN 4140-01-240-7531
NSN 6645-01-196-8616
NSN 2925-00-596-9775
NSN 6135-01-442-7275
NSN 6645-01-012-5972
NSN 2925-00-253-1655
NSN 5998-00-153-8444
NSN 6135-01-067-8331
NSN 5945-01-108-1490
NSN 6650-01-646-1643
NSN 6145-01-085-3984
NSN 2925-01-660-0669