A nut having 6 flat sides and an integral washer which extends beyond the flats or periphery.
NSN 6240-01-521-4822
NSN 6320-00-164-4087
NSN 5895-00-597-8725
NSN 6610-01-152-9240
NSN 6650-01-197-0587
NSN 5960-01-142-1995
NSN 6685-01-524-4348
NSN 5930-00-248-6339
NSN 5945-01-041-9241
NSN 6110-01-148-9067
NSN 6130-00-141-8317
NSN 6620-00-004-5466