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 5996-01-183-6551
NSN 5965-01-250-0446
NSN 6130-00-343-1660
NSN 7035-00-421-8710
NSN 6240-01-084-3952
NSN 6105-01-114-4452
NSN 5835-01-227-4752
NSN 6685-00-020-2743
NSN 5996-01-322-9007
NSN 5990-01-492-1114
NSN 6620-01-606-8964
NSN 5930-00-594-0152