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 5925-00-402-7768
NSN 6130-00-654-5833
NSN 5996-01-447-4916
NSN 5835-01-362-8367
NSN 5855-01-644-3271
NSN 6130-01-442-6052
NSN 5920-00-229-1812
NSN 6645-01-220-2838
NSN 6130-00-220-5791
NSN 5990-01-411-5930
NSN 5835-01-561-2278
NSN 6135-01-501-5376