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 5835-01-384-3206
NSN 6145-01-425-7810
NSN 6685-00-501-6501
NSN 6685-00-707-4842
NSN 5935-01-153-9598
NSN 5960-00-315-0358
NSN 5985-01-029-7543
NSN 6110-00-950-6065
NSN 6685-01-268-2899
NSN 5990-01-408-6554
NSN 5975-01-328-5133
NSN 6620-01-328-7059