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 6685-01-103-4599
NSN 5920-01-165-9908
NSN 6105-01-461-3104
NSN 6135-01-438-9450
NSN 5925-00-731-7710
NSN 5925-00-777-4083
NSN 6150-01-289-1283
NSN 5996-01-469-6848
NSN 5998-01-560-1707
NSN 6150-00-251-3805
NSN 6220-00-831-4558
NSN 6650-00-021-9555