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 4140-01-534-5450
NSN 5910-01-170-5074
NSN 6240-00-982-9792
NSN 5975-01-581-3429
NSN 5925-01-154-0236
NSN 6150-01-229-2085
NSN 5855-00-298-0261
NSN 6645-00-397-2210
NSN 6150-01-061-2754
NSN 6645-01-045-4088
NSN 5990-01-449-7090
NSN 5930-00-636-4998