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 5985-01-370-4978
NSN 6130-01-355-5109
NSN 6620-00-409-4975
NSN 6650-00-006-7136
NSN 5965-01-388-5296
NSN 6135-00-932-3136
NSN 5965-01-005-0341
NSN 6685-00-204-6037
NSN 6105-01-141-6912
NSN 6130-01-112-1103
NSN 5998-00-455-9905
NSN 5920-01-465-2184