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 5905-00-087-4286
NSN 5935-01-433-5177
NSN 6650-00-185-8344
NSN 5910-01-184-3535
NSN 6610-01-167-8747
NSN 6240-01-438-1157
NSN 6145-00-611-4834
NSN 6130-00-283-4329
NSN 6650-01-483-0938
NSN 5990-00-799-2796
NSN 6150-01-263-8786
NSN 5996-01-576-7375