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 6110-01-365-4348
NSN 5975-01-048-1565
NSN 5935-01-377-4311
NSN 6610-01-608-0004
NSN 5915-01-150-0246
NSN 6685-01-201-1018
NSN 5985-00-049-8929
NSN 5945-01-545-5579
NSN 5965-01-344-8592
NSN 6610-01-433-0756
NSN 5920-01-228-4384
NSN 5985-01-218-9970