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 2925-01-297-2315
NSN 6620-01-448-1423
NSN 5855-01-452-1406
NSN 6135-00-962-4111
NSN 6240-01-357-4293
NSN 6610-01-641-7834
NSN 5998-00-067-8011
NSN 6145-00-284-1514
NSN 5960-01-354-0762
NSN 6645-01-296-4223
NSN 6145-01-431-8803
NSN 6685-00-248-6990