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 5998-01-367-2905
NSN 5985-01-601-2352
NSN 5855-00-918-1622
NSN 6105-00-413-8097
NSN 6650-01-463-2274
NSN 5915-01-408-6647
NSN 5910-01-473-5130
NSN 2925-01-444-2061
NSN 6620-01-406-3584
NSN 5998-00-498-3977
NSN 6240-00-421-5368
NSN 5999-00-670-4673