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 6145-01-241-9221
NSN 4140-01-142-3192
NSN 5915-01-382-3375
NSN 6130-01-546-9261
NSN 6240-01-383-1576
NSN 5910-00-146-5774
NSN 5895-01-542-7001
NSN 6130-01-188-6040
NSN 6610-00-142-9678
NSN 6145-01-550-9633
NSN 4140-01-184-3488
NSN 5985-01-183-2127