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 5835-00-148-9719
NSN 5945-01-027-2258
NSN 4140-01-495-1352
NSN 5915-01-519-3287
NSN 6220-00-752-8479
NSN 6220-01-163-8775
NSN 6620-01-145-1278
NSN 5855-01-391-7077
NSN 6650-01-466-2704
NSN 6240-01-394-5320
NSN 5910-01-142-2688
NSN 5945-00-498-7049