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 5915-01-423-4642
NSN 5920-01-578-6279
NSN 5996-01-547-3452
NSN 6105-01-487-4437
NSN 5895-00-349-6061
NSN 5935-00-114-1068
NSN 5960-00-584-4553
NSN 6220-01-088-6604
NSN 6650-01-166-5025
NSN 5990-00-573-3325
NSN 5895-01-499-9906
NSN 6645-01-406-6077