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 5855-01-418-6303
NSN 5910-01-381-0709
NSN 5950-00-232-0742
NSN 5950-01-458-5977
NSN 6130-00-013-2131
NSN 6650-00-221-9425
NSN 6145-01-092-1086
NSN 6220-01-417-1847
NSN 5985-01-420-6195
NSN 5905-01-605-1283
NSN 6650-00-059-6268
NSN 6685-00-404-8444