A nut having 6 flat sides and an integral washer which extends beyond the flats or periphery.
NSN 5990-01-544-0364
NSN 6650-00-190-5158
NSN 2925-00-526-4541
NSN 5965-01-508-1093
NSN 6130-01-579-5418
NSN 6645-01-285-8304
NSN 4140-00-246-4969
NSN 6610-01-305-8863
NSN 6320-00-593-0379
NSN 6650-01-149-6621
NSN 5910-01-213-7516
NSN 5990-00-174-6695