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 5945-01-592-1531
NSN 5998-00-797-9574
NSN 5998-00-596-8869
NSN 6105-00-193-8150
NSN 2925-01-212-1040
NSN 6685-00-241-5054
NSN 5999-00-163-6260
NSN 5910-00-075-0977
NSN 5985-01-650-8657
NSN 6105-01-467-5468
NSN 6145-01-205-5936
NSN 5855-00-937-5320