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 
Italy 
Turkey Classification: Gaskets, washers and other seals, of vulcanized rubber other than hard rubber
NSN 6645-01-417-3524
NSN 6150-01-359-8517
NSN 5985-00-988-6835
NSN 5925-01-217-8406
NSN 6145-00-738-5601
NSN 6135-01-471-7325
NSN 5945-01-416-9259
NSN 6645-00-246-4934
NSN 5920-01-395-0374
NSN 5895-01-549-3358
NSN 5996-01-026-8807
NSN 7035-01-643-9932