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 6240-00-849-5026
NSN 6220-01-318-4996
NSN 5930-00-935-4539
NSN 2925-01-384-4139
NSN 5985-01-056-5050
NSN 5905-00-597-8280
NSN 5945-01-656-5877
NSN 5915-00-457-9296
NSN 5920-01-632-9399
NSN 6110-00-516-8645
NSN 6650-00-249-5553
NSN 5960-01-623-9896