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 6220-00-972-7933
NSN 5990-00-444-0612
NSN 5990-01-386-5561
NSN 6320-01-600-5808
NSN 5945-00-918-8808
NSN 5910-00-388-6737
NSN 5960-00-104-5955
NSN 5945-01-468-1355
NSN 7035-01-492-6799
NSN 6645-01-005-1885
NSN 5975-01-381-1086
NSN 5965-00-061-1061