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 7035-01-429-7954
NSN 5895-00-689-2990
NSN 7035-00-631-3782
NSN 5945-01-163-0688
NSN 6685-01-208-9946
NSN 5965-00-052-9184
NSN 5965-01-537-0023
NSN 6135-01-290-6487
NSN 7035-01-194-6332
NSN 5975-01-485-8116
NSN 5935-00-098-1782
NSN 4140-00-368-4261