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 5998-01-202-8949
NSN 6240-00-961-8074
NSN 7035-00-455-7666
NSN 5925-01-067-7241
NSN 5835-01-647-6426
NSN 4140-00-200-9082
NSN 6150-01-299-8884
NSN 5915-01-136-3707
NSN 5895-01-184-9975
NSN 6685-01-501-1312
NSN 5910-01-392-4064
NSN 6220-00-106-7541