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 4140-01-394-6982
NSN 6650-01-524-2105
NSN 6135-01-547-3983
NSN 6320-01-267-5117
NSN 5895-01-037-3154
NSN 6645-00-479-9334
NSN 5945-01-022-9695
NSN 5950-01-415-5150
NSN 5945-01-401-5323
NSN 5975-00-516-9335
NSN 6145-00-185-4515
NSN 4140-00-918-5162