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 5910-01-413-8830
NSN 5835-00-155-1379
NSN 6135-01-175-7311
NSN 5905-01-386-5742
NSN 5960-01-480-0994
NSN 5960-01-089-2953
NSN 5925-01-232-1318
NSN 5855-00-165-3093
NSN 6150-00-419-6008
NSN 5960-00-219-6148
NSN 6645-01-364-0867
NSN 6220-01-261-2488