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 5855-01-653-4319
NSN 6220-01-550-3646
NSN 5895-01-422-1041
NSN 5925-01-536-3867
NSN 5835-00-740-0246
NSN 5895-00-065-1960
NSN 6130-01-139-3701
NSN 6110-01-502-7005
NSN 6320-01-366-5157
NSN 5990-00-049-8887
NSN 5998-01-044-5108
NSN 5965-01-452-4189