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 5910-00-831-0350
NSN 5996-01-472-2006
NSN 5996-00-061-0336
NSN 5855-00-688-9954
NSN 5930-00-144-4994
NSN 5835-01-368-1013
NSN 2925-01-572-0539
NSN 6145-00-266-8453
NSN 5855-01-444-5248
NSN 5935-00-900-0331
NSN 5925-01-225-5236
NSN 5985-01-277-8979