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 5905-00-913-4941
NSN 5999-00-578-2728
NSN 6150-00-314-5242
NSN 6130-01-222-0475
NSN 7035-01-407-6413
NSN 5999-00-188-3778
NSN 7035-01-281-3642
NSN 5945-01-062-0800
NSN 6220-00-686-5328
NSN 5998-00-134-8177
NSN 5996-01-348-9844
NSN 5855-01-487-8872