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 5950-01-574-2938
NSN 6240-01-540-5980
NSN 7035-01-068-4175
NSN 2925-01-423-3003
NSN 6685-00-125-9619
NSN 5920-01-048-0766
NSN 5935-01-372-2734
NSN 6645-00-935-7046
NSN 6685-01-460-9428
NSN 6320-01-429-5728
NSN 5855-00-494-9581
NSN 5835-01-386-4027