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 5855-01-546-9423
NSN 6135-00-900-2139
NSN 6610-01-152-1463
NSN 6610-01-573-5949
NSN 7035-00-703-3535
NSN 6650-01-443-1476
NSN 5925-01-461-7586
NSN 5960-01-331-3817
NSN 6685-00-523-9415
NSN 5930-00-780-2047
NSN 6650-01-486-3964
NSN 5835-01-449-7511