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.)
Brazil 
France 
Greece Classification: Nuts of iron or steel
NSN 5960-00-231-3767
NSN 5910-01-596-6960
NSN 5915-01-329-1762
NSN 5990-01-200-2800
NSN 5975-01-412-9421
NSN 2925-01-525-8212
NSN 6135-01-511-1975
NSN 6110-01-067-7677
NSN 5975-01-501-3284
NSN 5905-01-083-0644
NSN 6220-01-602-2398
NSN 6105-01-545-2776