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 6135-01-584-0941
NSN 5835-01-632-6627
NSN 5998-01-147-3935
NSN 5910-00-816-8622
NSN 6650-00-087-6428
NSN 5910-01-108-0054
NSN 5999-01-055-7498
NSN 5990-00-067-6791
NSN 6650-01-119-0718
NSN 5915-00-088-1563
NSN 5945-00-419-0184
NSN 6240-01-613-0089