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 5895-01-044-5425
NSN 6240-00-872-3365
NSN 6645-01-165-3785
NSN 6240-00-982-9792
NSN 6685-00-850-7070
NSN 6130-01-124-2630
NSN 5935-00-513-9606
NSN 5920-01-511-3996
NSN 5985-01-647-4721
NSN 5895-01-437-2384
NSN 6150-01-041-0533
NSN 6650-01-442-7893