Nut, hex, heavy duty (requested name)
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.)
NSN 6105-01-463-7185
NSN 5935-01-634-0668
NSN 5925-00-254-0562
NSN 2925-01-472-4423
NSN 7035-00-117-0418
NSN 6620-00-635-7347
NSN 5905-01-554-7350
NSN 7035-01-657-1689
NSN 5915-00-145-4936
NSN 5920-01-083-9912
NSN 6620-01-487-0605
NSN 6135-00-900-2139