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 6650-01-112-0453
NSN 5945-01-152-2780
NSN 6150-01-629-9094
NSN 6685-01-572-9718
NSN 5930-01-631-4560
NSN 4140-01-150-9209
NSN 6135-00-906-0984
NSN 5965-00-471-5018
NSN 6610-01-462-5980
NSN 4140-01-062-3818
NSN 2925-01-422-1542
NSN 5950-00-574-3066