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 6240-01-043-9074
NSN 5855-01-079-1259
NSN 5855-00-237-4088
NSN 5985-01-054-4816
NSN 5835-00-092-1136
NSN 6320-01-280-5091
NSN 6240-01-203-2107
NSN 5895-01-559-0501
NSN 6610-00-953-4944
NSN 5985-00-949-3316
NSN 6105-01-382-2349
NSN 2925-00-146-0179