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 5910-01-096-1946
NSN 5965-00-698-0433
NSN 5965-00-840-6542
NSN 6150-00-865-7685
NSN 5996-01-099-4588
NSN 6220-00-209-9630
NSN 5895-00-799-5181
NSN 5835-00-013-0905
NSN 5905-00-938-1406
NSN 6130-01-191-8752
NSN 5950-01-042-2947
NSN 5835-01-064-6024