A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. 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.)
Dept. of the Navy NSN 5960-01-469-8421
NSN 6320-01-493-4472
NSN 5990-01-154-7296
NSN 5965-00-113-9748
NSN 5905-01-641-2786
NSN 6645-01-367-2581
NSN 5945-00-195-4679
NSN 6610-01-416-8384
NSN 6220-01-599-9731
NSN 5855-01-260-7445
NSN 6110-01-571-8717
NSN 6145-01-400-1030