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 6110-01-633-9660
NSN 5930-01-094-7222
NSN 5895-01-417-8475
NSN 6105-01-168-0665
NSN 6685-00-892-5669
NSN 5925-00-275-7599
NSN 7035-01-493-4173
NSN 5950-00-247-0985
NSN 5910-01-144-7471
NSN 5910-01-617-9446
NSN 6110-01-447-1954
NSN 5930-01-139-3328