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 6135-00-900-2139
NSN 5895-01-542-8918
NSN 5960-01-466-4153
NSN 6150-00-960-3256
NSN 5835-01-301-0022
NSN 5910-01-548-6551
NSN 5895-00-122-4747
NSN 5996-00-098-3864
NSN 6105-00-089-6824
NSN 6220-00-150-0039
NSN 6240-00-498-2034
NSN 6110-01-514-2879