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 5910-00-270-6876
NSN 5930-01-383-4795
NSN 5999-01-458-8369
NSN 5895-01-253-8074
NSN 6685-01-255-4039
NSN 6135-01-530-8136
NSN 5905-01-193-0617
NSN 6220-00-875-6586
NSN 6130-00-056-9199
NSN 5965-00-888-2643
NSN 5835-01-017-3860
NSN 6320-01-512-2031