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 6240-01-415-3014
NSN 5999-01-130-5216
NSN 5915-00-420-1557
NSN 5990-01-307-4489
NSN 6645-00-650-3405
NSN 5960-01-224-3850
NSN 5965-01-525-6731
NSN 5905-00-336-0438
NSN 5925-01-238-9414
NSN 5985-00-107-7928
NSN 5960-01-564-5044
NSN 5965-01-373-0873