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 6650-01-120-6231
NSN 6130-00-021-5372
NSN 6610-00-186-9180
NSN 5930-01-040-2734
NSN 5950-00-164-7168
NSN 5930-00-908-4745
NSN 5835-00-733-9145
NSN 6650-00-995-8015
NSN 5950-01-532-5306
NSN 6610-01-102-2256
NSN 6220-00-958-9830
NSN 6685-01-085-7301