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 6320-01-072-2073
NSN 5915-01-507-4033
NSN 5930-01-106-0771
NSN 5935-01-141-6290
NSN 6135-01-437-6409
NSN 5975-01-257-3494
NSN 6650-01-231-6728
NSN 6685-01-202-7823
NSN 5920-00-084-0988
NSN 5985-01-219-5297
NSN 6620-00-770-9794
NSN 6105-01-050-9376