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 7035-01-408-8698
NSN 6130-00-161-7432
NSN 5915-01-206-1208
NSN 5925-00-275-7599
NSN 5920-00-409-2312
NSN 5998-01-135-2363
NSN 5915-01-373-6065
NSN 5935-01-524-8901
NSN 6320-01-618-3835
NSN 5998-01-595-6073
NSN 5930-01-223-2347
NSN 6150-00-165-5816