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 6650-00-492-9503
NSN 5835-00-431-4451
NSN 5985-00-758-2056
NSN 6620-01-556-1695
NSN 5935-01-646-6766
NSN 5920-01-296-5461
NSN 6150-01-487-4525
NSN 5905-01-032-4866
NSN 5975-01-004-2009
NSN 5975-01-364-0312
NSN 5920-01-632-4842
NSN 6130-01-622-3129