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 5935-01-503-7384
NSN 6145-01-480-8688
NSN 7035-00-915-5798
NSN 5965-01-146-0579
NSN 6145-00-583-3940
NSN 6645-01-575-4181
NSN 5960-00-392-6291
NSN 5985-01-189-5151
NSN 6610-01-018-2431
NSN 5998-01-497-0797
NSN 5996-00-006-8128
NSN 5930-01-010-3283