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 5930-00-375-5892
NSN 5999-01-134-9661
NSN 6610-01-414-1755
NSN 2925-01-511-2667
NSN 6110-01-216-6524
NSN 6150-01-554-5436
NSN 5999-00-819-1292
NSN 4140-00-219-3146
NSN 5910-01-434-8866
NSN 6110-01-622-1983
NSN 6650-01-532-2513
NSN 6130-01-487-3758