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 6620-01-527-4423
NSN 5910-01-454-2519
NSN 5935-00-337-0445
NSN 5915-01-459-5814
NSN 5960-01-398-9538
NSN 6135-01-334-3935
NSN 5905-00-141-0596
NSN 5999-01-372-8165
NSN 6145-01-604-1260
NSN 5950-00-216-7548
NSN 5905-00-243-9039
NSN 6105-00-643-4975