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 5975-00-798-8166
NSN 6685-01-079-2817
NSN 6130-00-192-1721
NSN 6130-00-829-3876
NSN 5930-00-208-4266
NSN 5935-01-398-8309
NSN 6240-01-381-6815
NSN 6645-00-309-0447
NSN 5985-00-654-9744
NSN 6105-01-544-1544
NSN 6240-00-306-9214
NSN 5930-01-455-8720