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 Air Force 
Germany 
Italy Classification: Cotters, cotter-pins, washers and similar articles, of aluminum
NSN 5835-01-362-0305
NSN 6240-01-204-6639
NSN 6145-01-362-0089
NSN 6610-01-267-1565
NSN 6610-01-010-4516
NSN 6135-01-139-1700
NSN 5935-01-492-4663
NSN 5999-00-518-1007
NSN 5975-01-391-5306
NSN 6220-01-509-3617
NSN 6685-01-631-2998
NSN 7035-01-348-1257