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 5915-01-094-6921
NSN 6610-01-456-5234
NSN 5985-01-386-6177
NSN 6135-00-016-0071
NSN 6685-00-848-6353
NSN 6685-00-925-7491
NSN 6650-01-457-0980
NSN 6320-01-115-4404
NSN 5990-00-140-1159
NSN 5985-01-597-8651
NSN 5965-01-386-2988
NSN 6240-01-641-9347