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 5945-01-618-6395
NSN 5835-00-284-0882
NSN 6620-00-586-6460
NSN 5935-01-477-9883
NSN 5990-01-579-2327
NSN 6145-01-558-1889
NSN 5920-01-150-3499
NSN 6110-01-607-4079
NSN 5998-00-297-2431
NSN 6240-01-641-4662
NSN 5925-01-079-3678
NSN 5915-01-381-0746