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 
Greece Classification: Washers other than lock washers, iron or steel
NSN 6220-01-121-7391
NSN 5960-01-563-6975
NSN 2925-01-271-8727
NSN 6220-01-003-3765
NSN 5925-00-149-2855
NSN 5950-01-007-8556
NSN 6610-01-164-8469
NSN 6130-00-484-9291
NSN 5935-01-346-6845
NSN 5975-00-962-7517
NSN 5975-01-089-9399
NSN 2925-00-701-9991