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 5895-00-707-1376
NSN 6220-01-250-4021
NSN 6150-00-018-6263
NSN 5999-01-079-0868
NSN 7035-01-327-4017
NSN 5915-01-141-6726
NSN 5950-00-104-5908
NSN 5996-01-210-9190
NSN 5990-01-623-0082
NSN 6220-00-777-2355
NSN 5855-01-179-2702
NSN 5905-01-194-0082