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 5920-00-161-2813
NSN 6110-01-492-1714
NSN 6240-00-299-9819
NSN 5915-01-550-4044
NSN 6645-01-608-1134
NSN 6650-01-469-1864
NSN 6150-01-582-2354
NSN 5999-00-022-9130
NSN 6130-00-148-8784
NSN 5835-00-711-3371
NSN 6620-01-029-3705
NSN 6610-00-590-3651