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 5996-01-027-1729
NSN 5985-01-281-7333
NSN 7035-00-140-0474
NSN 5985-01-196-6144
NSN 5950-01-303-9983
NSN 6220-01-352-5425
NSN 5950-00-789-4717
NSN 6685-01-023-8731
NSN 5915-01-207-1416
NSN 2925-01-233-8545
NSN 5960-01-525-1690
NSN 6130-00-276-0658