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 4140-00-344-8601
NSN 6130-01-208-1861
NSN 6685-01-501-5362
NSN 5895-00-586-7739
NSN 5965-00-768-4366
NSN 5910-01-407-2518
NSN 6135-01-010-0891
NSN 6320-01-600-5808
NSN 5835-01-534-3172
NSN 5985-00-086-6234
NSN 6130-01-327-4594
NSN 5996-01-444-4547