A circular shaped item with an aperture manufactured to predetermined dimensions and designed for use as a seal in stuffing boxes, packing nuts, and the like. It may be (1) any nonmetallic molded or formed ring (except solid (without joint) rings having a square or rectangular cross section); or (2) any shredded metal or metal foil type metallic or semimetallic rings. Excludes felt items but includes multimaterial items in which one of the materials is felt. For solid (without joints) nonmetallic items with a square or rectangular cross section, see washer (as modified) and gasket. For rubber items specifically designed for weather-proofing doors, windows, chests, and the like see seal, nonmetallic angle; seal, nonmetallic channel; and seal, nonmetallic, special shaped section. For circular (with aperature) nonmetallic items with a solid round cross-section see o-ring. Excludes cup, compression; gasket; washer (as modified); and felt, mechanical, preformed.
Australia 
Canada 
United Kingdom Classification: Gaskets,washers & other seals
NSN 4140-01-559-0568
NSN 5920-01-089-7903
NSN 5925-00-730-2777
NSN 5985-01-254-4534
NSN 5915-01-598-6156
NSN 5835-01-031-7265
NSN 6320-01-096-6649
NSN 5920-00-529-0618
NSN 6240-00-829-2595
NSN 5920-01-459-2299
NSN 6135-01-252-0315
NSN 5895-01-258-2363