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 5975-01-170-4598
NSN 5998-01-360-8592
NSN 5960-01-167-8796
NSN 2925-01-148-5810
NSN 5998-00-168-4283
NSN 5930-01-476-1880
NSN 5835-00-466-8544
NSN 5915-01-633-9845
NSN 5990-01-534-8609
NSN 5996-01-598-9071
NSN 5985-01-471-0229
NSN 6110-00-079-8508