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 6145-01-488-4556
NSN 6620-01-552-2889
NSN 5930-00-942-2949
NSN 4140-00-555-3856
NSN 5930-01-266-6272
NSN 5855-01-573-4289
NSN 5930-01-211-6123
NSN 2925-01-342-1712
NSN 6130-00-928-0642
NSN 6110-01-615-1371
NSN 5998-01-327-2995
NSN 6220-01-446-6430