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 5998-01-654-8885
NSN 7035-01-155-0153
NSN 5945-00-731-0179
NSN 6610-01-371-3006
NSN 6620-01-026-0346
NSN 6135-01-008-4595
NSN 5965-00-501-7835
NSN 5999-01-459-8452
NSN 4140-00-090-4174
NSN 6220-01-155-0628
NSN 5990-01-254-2936
NSN 6320-01-526-5534