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 5895-01-386-6972
NSN 6130-01-090-0631
NSN 5925-00-279-1353
NSN 5950-01-372-0701
NSN 6110-01-392-6084
NSN 6220-00-775-2384
NSN 5895-01-147-5688
NSN 6240-01-032-9952
NSN 6105-01-163-7655
NSN 6145-00-318-9206
NSN 5975-00-990-7024
NSN 2925-00-614-1758