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 5965-01-358-6859
NSN 6130-01-447-9788
NSN 6240-01-269-0375
NSN 6320-01-369-5014
NSN 6150-01-122-2275
NSN 5855-00-631-4565
NSN 6110-01-472-2953
NSN 5930-01-411-6201
NSN 2925-00-233-5644
NSN 5985-00-500-6366
NSN 5895-01-304-4249
NSN 5925-00-343-6747