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 5920-01-401-5315
NSN 6685-01-192-3051
NSN 4140-01-134-9838
NSN 5835-01-485-1408
NSN 5910-00-477-5216
NSN 6610-00-314-2605
NSN 5999-01-237-5874
NSN 6145-00-010-5135
NSN 5925-01-390-5119
NSN 6105-01-322-8246
NSN 5950-01-246-3984
NSN 5950-00-239-5261