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 6685-01-275-5340
NSN 5950-01-163-4040
NSN 5990-01-381-9526
NSN 5998-01-487-3620
NSN 5945-01-409-0879
NSN 6240-00-057-2887
NSN 7035-00-834-2090
NSN 5960-00-814-4591
NSN 5910-01-231-2672
NSN 4140-01-409-1434
NSN 5910-01-426-1426
NSN 2925-00-933-0200