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 6105-01-206-1044
NSN 5920-01-200-6655
NSN 5910-01-146-5438
NSN 6145-00-236-0012
NSN 6130-01-598-4336
NSN 5965-01-328-9765
NSN 6150-01-195-6648
NSN 4140-01-389-0595
NSN 6105-01-430-5401
NSN 5950-01-071-9574
NSN 5960-01-386-3855
NSN 5835-01-173-1578