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 6220-01-094-5551
NSN 5855-01-085-5354
NSN 6135-00-973-5632
NSN 5920-01-605-1604
NSN 5945-01-175-7318
NSN 5950-01-329-0616
NSN 5920-01-179-5289
NSN 5960-01-310-3863
NSN 6610-01-074-2883
NSN 5950-00-581-9999
NSN 5985-01-317-3143
NSN 7035-01-145-5059