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 5915-00-247-8770
NSN 5855-01-205-7030
NSN 6130-00-005-8100
NSN 6150-01-457-8970
NSN 2925-00-782-1498
NSN 5985-00-845-1962
NSN 5930-01-367-2520
NSN 7035-00-270-5519
NSN 6645-01-595-1160
NSN 5960-01-262-0359
NSN 6150-00-623-9652
NSN 6220-01-314-5439