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 5935-01-061-7526
NSN 6620-01-241-2306
NSN 5915-01-059-6755
NSN 5985-00-970-9100
NSN 7035-01-227-2546
NSN 5930-01-184-7783
NSN 6320-01-411-7456
NSN 5945-01-365-1639
NSN 6220-01-321-7655
NSN 5910-00-958-3255
NSN 7035-00-803-3056
NSN 4140-01-028-0629