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 5855-01-273-0927
NSN 5996-00-775-2230
NSN 5910-01-503-2570
NSN 5960-01-536-6398
NSN 5930-01-278-0650
NSN 5975-01-128-7956
NSN 5930-01-209-3025
NSN 5935-00-256-8779
NSN 5990-00-258-0228
NSN 6650-00-555-1061
NSN 5990-01-463-5400
NSN 5935-01-544-6029