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 5990-01-095-8866
NSN 5910-00-356-7824
NSN 6150-01-399-0651
NSN 5920-01-392-1484
NSN 5915-01-501-9597
NSN 4140-01-350-4475
NSN 5990-01-159-5988
NSN 5999-01-143-8460
NSN 5905-01-502-9310
NSN 5910-01-485-8128
NSN 6105-00-089-1583
NSN 5905-00-337-0447