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 5855-01-450-5609
NSN 5998-01-222-0641
NSN 5965-01-656-3038
NSN 7035-00-529-3128
NSN 5945-00-788-1183
NSN 5835-01-597-4820
NSN 5910-00-199-5467
NSN 4140-00-200-9082
NSN 5910-00-420-3930
NSN 5999-01-276-3028
NSN 2925-00-265-7539
NSN 6105-01-024-9425