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 6620-01-103-3556
NSN 6135-01-035-1871
NSN 5998-01-304-4005
NSN 5920-01-440-5629
NSN 6150-01-394-5915
NSN 5975-00-228-3869
NSN 6320-01-412-2973
NSN 7035-01-182-1086
NSN 6620-00-690-8905
NSN 5965-01-477-6665
NSN 6110-01-485-5687
NSN 6685-01-083-2830