A flat metal or plastic item of various peripheral shapes having a solid (not laminated) cross-section. It is designed to maintain a predetermined distance between two surfaces. For round items without a hole having a solid rectangular cross-section use disk, solid, plain. For round or hexagonal items with only one hole centrally located and with the length (thickness) exceeding 25 percent of the outside diameter or distance across peripheral flats, see spacer, sleeve. The thickness between the two parallel bearing surfaces must be 0.006 inch, (0.152 mm) or more for items less than 1/4 inch (6.35 mm) across the peripheral diameter, or smallest overall outside dimension, or must be 0.016 inch (0.406 mm) or more for items 1/4 inch (6.35 mm) or greater across the peripheral diameter or smallest overall outside dimension. For items with a thickness less than those indicated above, see shim. For items with one hole centrally located conforming to the above dimensional criteria use washer, flat or spacer, ring as applicable. When thickness and/or outside diameter or smallest overall outside dimension is designated as a tolerance/dimension the maximum dimension will be used to determine compliance. Excludes gasket; insulator (as modified) and mounting pad, electrical-electronic component.
Dept. of the Army 
Dept. of the Air Force 
U.s. Marine Corps 
Dept. of the Navy Classification: Parts of armored fighting vehicles,motorized, whether or not fitted with weapons
NSN 6645-01-352-6583
NSN 6105-01-376-2214
NSN 5905-01-132-5000
NSN 5895-00-788-9707
NSN 6110-00-068-8700
NSN 5905-01-099-0925
NSN 7035-01-150-6303
NSN 6645-01-620-4837
NSN 6620-00-506-0112
NSN 6685-00-284-2244
NSN 6150-01-659-3987
NSN 5895-01-500-4709