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 5990-01-575-3275
NSN 5960-00-770-3701
NSN 6610-01-003-8791
NSN 5996-00-255-4097
NSN 5855-01-363-6012
NSN 6105-01-384-6172
NSN 6610-00-727-9918
NSN 5925-01-092-6395
NSN 5895-00-491-1296
NSN 5950-01-550-0411
NSN 5915-00-334-3008
NSN 5965-01-157-7732