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 5905-00-469-7390
NSN 2925-00-172-9264
NSN 4140-01-069-4576
NSN 5925-01-642-4915
NSN 5910-00-687-1254
NSN 5920-00-903-0031
NSN 6105-01-564-5316
NSN 5960-01-350-2925
NSN 6110-01-246-4347
NSN 5905-01-177-7279
NSN 5835-00-562-7524
NSN 6105-01-456-4488