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 5925-00-824-0329
NSN 6135-01-422-1440
NSN 5925-00-197-4329
NSN 6145-01-201-9544
NSN 6110-00-132-4048
NSN 6110-01-519-9131
NSN 5960-00-519-9056
NSN 5945-00-950-5667
NSN 5960-01-328-8248
NSN 6130-01-147-5594
NSN 6650-01-355-6608
NSN 6645-00-507-5544