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 6620-01-168-1615
NSN 5975-01-142-3190
NSN 5835-01-602-0311
NSN 4140-01-127-4674
NSN 6240-01-497-7823
NSN 6105-00-723-7343
NSN 5990-00-236-0831
NSN 5996-01-572-8860
NSN 6610-01-205-8340
NSN 6130-00-135-9095
NSN 4140-01-496-3764
NSN 5920-00-468-3074