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 4140-01-480-9575
NSN 6135-00-643-4843
NSN 6240-00-144-4693
NSN 5895-01-407-8948
NSN 5925-01-211-6660
NSN 5950-01-431-9818
NSN 2925-01-226-6126
NSN 6220-01-219-9670
NSN 5925-01-474-6358
NSN 6650-00-471-1117
NSN 5905-00-197-7674
NSN 6650-01-580-1901