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 5935-01-307-7096
NSN 5990-00-111-3614
NSN 6620-01-385-6172
NSN 2925-01-415-0264
NSN 6220-01-217-1517
NSN 6105-01-611-0848
NSN 6220-01-207-8068
NSN 4140-00-189-0235
NSN 5998-01-247-9888
NSN 5960-01-283-0308
NSN 6645-00-279-1777
NSN 6620-01-415-5803