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 6220-00-450-7342
NSN 5960-01-495-0859
NSN 5920-01-115-4164
NSN 5965-00-071-0562
NSN 6685-00-724-2962
NSN 5960-01-506-7039
NSN 6130-01-393-5403
NSN 5965-01-500-2468
NSN 5910-01-614-4092
NSN 5965-00-324-2428
NSN 5950-00-869-1636
NSN 6150-01-251-1420