A nut, flat on top and bottom, having 4 flat sides. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
NSN 5950-00-726-2597
NSN 2925-01-049-8906
NSN 5999-00-098-8528
NSN 6620-00-342-9843
NSN 5996-01-285-2353
NSN 6145-00-614-9302
NSN 6145-01-226-9662
NSN 6130-01-570-9603
NSN 5965-00-934-3495
NSN 5935-00-767-4319
NSN 6220-01-005-4322
NSN 6150-01-461-3256