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 5945-00-159-6774
NSN 5835-01-426-6573
NSN 6130-01-461-3145
NSN 6650-01-472-3955
NSN 5990-01-497-0093
NSN 5920-01-487-4195
NSN 5965-01-028-2587
NSN 5998-01-414-4451
NSN 4140-00-224-2133
NSN 5895-01-342-6615
NSN 4140-01-329-6293
NSN 6145-00-165-3869