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 5835-01-599-0649
NSN 5895-00-157-5981
NSN 5895-01-359-9188
NSN 6240-00-252-7138
NSN 6645-00-067-7070
NSN 6620-01-327-4111
NSN 6685-01-610-0872
NSN 5950-00-630-8993
NSN 4140-01-551-9540
NSN 6220-00-025-3697
NSN 5960-01-599-9821
NSN 6150-01-017-7688