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 6685-01-056-4379
NSN 6145-01-006-4046
NSN 5915-00-276-8332
NSN 5915-01-341-5695
NSN 6610-01-238-8712
NSN 5925-01-551-1265
NSN 5835-00-554-0399
NSN 6130-01-608-7915
NSN 6150-00-870-7127
NSN 6105-00-125-7964
NSN 6105-01-130-8285
NSN 5855-01-556-7421