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 Navy 
Singapore 
Turkey Classification: Copper screws, nuts, bolts, rivets, and other fasteners not threaded
NSN 6220-00-900-4439
NSN 6105-01-433-2404
NSN 5895-01-029-6225
NSN 6110-00-250-5949
NSN 6240-01-221-9093
NSN 5895-00-163-9608
NSN 5985-01-158-4468
NSN 5855-00-861-0006
NSN 5965-01-476-4228
NSN 6650-01-308-7284
NSN 5920-01-459-8493
NSN 6105-01-481-2581