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 6610-01-522-9882
NSN 5999-00-017-6957
NSN 5990-01-632-0969
NSN 2925-01-422-1542
NSN 5835-01-005-8564
NSN 6150-01-531-8250
NSN 6110-01-400-4207
NSN 6610-01-200-6861
NSN 5835-01-436-6549
NSN 6105-01-271-1538
NSN 5895-01-411-1211
NSN 5945-01-320-3313