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 5930-01-382-9642
NSN 5835-00-498-8189
NSN 6240-01-023-2013
NSN 5835-00-289-9080
NSN 6610-01-362-8686
NSN 5960-01-314-1822
NSN 6320-01-211-6578
NSN 5950-00-490-4396
NSN 6105-01-010-3512
NSN 6620-01-068-6224
NSN 5965-01-492-5695
NSN 5996-00-723-6743