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 5999-01-323-5807
NSN 6220-01-574-7537
NSN 5905-01-451-4205
NSN 5835-01-426-6573
NSN 6150-00-583-9878
NSN 6105-00-270-8078
NSN 6135-01-391-6515
NSN 5910-00-642-6484
NSN 6685-01-049-1017
NSN 5975-00-226-8429
NSN 5905-01-099-9496
NSN 5895-01-442-2688