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 2925-00-113-6146
NSN 6320-01-304-3639
NSN 5920-01-306-5053
NSN 5835-00-163-5111
NSN 5835-01-519-1153
NSN 5925-01-028-4085
NSN 5975-01-317-9794
NSN 6645-01-521-3180
NSN 6220-01-317-3283
NSN 5835-01-088-1787
NSN 6620-00-451-8783
NSN 5998-01-478-2188