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 5905-01-514-8166
NSN
NSN 5935-01-541-4597
NSN 6620-01-365-1499
NSN 6220-00-379-4044
NSN 6220-01-632-8217
NSN 6135-00-803-3012
NSN 5835-01-205-6614
NSN 5895-01-306-5568
NSN 5965-00-894-0015
NSN 6150-00-660-8331
NSN 6650-00-443-1000