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 5950-01-093-7191
NSN 5985-01-196-6144
NSN 5998-01-462-2625
NSN 5985-01-145-2577
NSN 5910-00-226-1113
NSN 6105-00-504-1742
NSN 5835-01-416-6455
NSN 6650-01-375-8207
NSN 5975-00-159-0969
NSN 5925-01-304-3279
NSN 5835-01-222-2437
NSN 5990-01-584-8363