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 5855-00-832-9341
NSN 5910-01-421-4805
NSN 5950-00-995-9261
NSN 5998-01-515-3136
NSN 6110-01-332-1665
NSN 5925-01-456-0763
NSN 6110-01-399-1176
NSN 6650-00-169-1866
NSN 6320-01-255-2096
NSN 6650-00-900-0049
NSN 6220-01-502-6030
NSN 6620-01-557-6512