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 5910-01-592-2746
NSN 5895-00-934-1372
NSN 5996-00-553-7348
NSN 6110-00-175-3661
NSN 5998-01-579-5852
NSN 6105-01-331-1555
NSN 5985-01-260-6622
NSN 6150-01-168-8290
NSN 5920-01-470-5835
NSN 6135-00-708-0892
NSN 6320-00-284-1524
NSN 5895-00-216-5849