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 5999-01-464-2241
NSN 5915-01-287-0655
NSN 6145-01-401-3713
NSN 5905-01-231-8791
NSN 5990-01-339-2811
NSN 6145-01-062-9820
NSN 4140-00-249-5603
NSN 5999-01-131-4680
NSN 6320-01-543-3238
NSN 4140-01-135-0998
NSN 6320-01-406-6098
NSN 5910-00-084-3575