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 6240-01-511-9778
NSN 6145-01-119-3176
NSN 5998-01-528-3649
NSN 5950-00-411-6197
NSN 6145-00-350-6657
NSN 5920-00-556-9993
NSN 5945-01-358-0407
NSN 5905-00-908-5788
NSN 2925-01-515-3032
NSN 6145-01-444-9955
NSN 2925-00-290-7052
NSN 2925-01-417-6815