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 5945-01-108-7418
NSN 6620-00-500-0041
NSN 6130-01-531-2288
NSN 6110-00-099-7113
NSN 5960-00-082-0493
NSN 2925-00-111-4097
NSN 5960-00-280-3759
NSN 6110-01-135-2027
NSN 6130-01-517-6490
NSN 6240-00-925-4662
NSN 5945-01-049-1995
NSN 6220-01-392-1429