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 6240-01-133-5607
NSN 4140-01-196-5984
NSN 5990-01-651-6364
NSN 5999-00-804-4488
NSN 6105-01-127-5663
NSN 6105-00-737-0829
NSN 6105-00-111-2546
NSN 5925-00-457-5364
NSN 6150-01-607-1273
NSN 6220-00-827-0227
NSN 5999-00-076-3271
NSN 5855-00-832-9341