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 5835-01-416-6455
NSN 5925-01-450-4759
NSN 6620-01-093-1383
NSN 6240-01-622-5961
NSN 6240-01-259-2090
NSN 6650-01-520-8701
NSN 5965-00-075-1485
NSN 5925-00-051-2003
NSN 5895-00-007-3791
NSN 6145-00-170-6872
NSN 6110-01-429-0008
NSN 6240-01-028-6737