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 5910-01-525-8024
NSN 5999-01-367-5918
NSN 5895-01-261-6457
NSN 5965-01-250-3214
NSN 5855-01-169-4275
NSN 5910-01-135-5060
NSN 5920-01-433-4343
NSN 6145-01-026-0030
NSN 6150-00-342-9765
NSN 6130-00-594-0516
NSN 5960-01-422-3269
NSN 4140-01-285-8753