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 5985-01-321-9498
NSN 5895-00-191-2146
NSN 5960-01-111-9918
NSN 5910-01-633-9963
NSN 5925-00-499-9220
NSN 5910-00-171-3414
NSN 5950-00-081-1763
NSN 6110-01-594-5292
NSN 6645-01-165-3785
NSN 6135-01-367-6203
NSN 5965-01-640-9777
NSN 6645-00-474-5689