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 6110-01-090-0417
NSN 6620-01-264-4904
NSN 5985-01-394-5373
NSN 6220-01-262-7302
NSN 5996-01-501-8729
NSN 6320-01-643-0850
NSN 6240-01-445-4232
NSN 6110-01-107-1021
NSN 5998-01-510-3837
NSN 5920-01-609-9878
NSN 5960-01-237-2336
NSN 4140-00-459-9045