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 6685-00-900-4246
NSN 5998-01-017-0045
NSN 6610-01-578-7771
NSN 5915-01-609-8605
NSN 5915-01-398-0633
NSN 5950-01-517-5765
NSN 6610-01-504-7622
NSN 5965-01-056-7225
NSN 6620-01-479-2352
NSN 5960-00-956-2318
NSN 6105-01-255-8138
NSN 5920-01-339-3977