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 5855-01-432-8750
NSN 5920-00-149-0013
NSN 6105-00-185-1579
NSN 6620-01-648-1594
NSN 6645-01-012-5972
NSN 5950-00-509-6305
NSN 5999-01-218-3944
NSN 4140-00-485-6139
NSN 5930-01-373-1716
NSN 5855-01-297-7847
NSN 6320-01-571-8974
NSN 5996-01-603-9740