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 5835-01-592-2350
NSN 6135-01-050-3194
NSN 6620-00-280-2874
NSN 6135-01-251-7054
NSN 6145-00-369-3880
NSN 5895-00-525-3295
NSN 5915-01-277-8571
NSN 6610-01-660-9082
NSN 6145-01-240-8174
NSN 6135-01-127-0173
NSN 5905-01-314-8083
NSN 5910-01-251-9592