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 5990-01-485-0260
NSN 6130-01-381-1713
NSN 5915-01-650-9353
NSN 6105-01-521-3582
NSN 4140-00-004-3668
NSN 6150-00-286-0827
NSN 5965-01-289-6436
NSN 5999-00-864-8854
NSN 6220-01-420-0390
NSN 5910-00-332-4286
NSN 6320-00-731-6134
NSN 5935-01-145-3735