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.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 5985-01-014-4071
NSN 5925-01-279-4140
NSN 5920-01-379-5044
NSN 6240-01-136-4694
NSN 4140-00-820-1173
NSN 2925-00-159-9003
NSN 4140-01-295-3226
NSN 6645-01-178-4936
NSN 6145-01-401-3713
NSN 5975-01-542-0438
NSN 6620-01-315-1857
NSN 5855-01-553-8437