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 5996-00-651-1656
NSN 6110-01-340-8849
NSN 5930-00-414-3296
NSN 5855-00-138-2386
NSN 6110-01-063-8309
NSN 6620-01-012-2852
NSN 6650-01-100-3185
NSN 6610-00-956-4464
NSN 5960-01-308-2474
NSN 5925-01-586-6554
NSN 6650-00-490-6993
NSN 6685-01-372-3393