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 5910-01-350-1202
NSN 5930-01-271-7854
NSN 6220-01-136-6839
NSN 6685-01-426-8929
NSN 6685-01-446-1095
NSN 6620-01-029-5572
NSN 6105-01-543-6107
NSN 5985-01-410-8737
NSN 6650-01-188-8028
NSN 5895-01-416-4337
NSN 6145-01-143-4324
NSN 5910-00-566-7058