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 5935-00-661-0825
NSN 6220-01-353-5851
NSN 6110-00-553-1853
NSN 6135-00-735-8530
NSN 4140-01-392-6165
NSN 6105-00-929-0515
NSN 5975-01-461-7821
NSN 5965-01-135-3679
NSN 5925-00-135-4276
NSN 5998-00-054-5450
NSN 5945-01-653-4194
NSN 6685-01-507-2911