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 5990-01-588-3999
NSN 5990-01-471-7858
NSN 6620-00-146-3465
NSN 5965-00-845-6325
NSN 6240-00-461-1451
NSN 6220-01-660-4029
NSN 5960-01-306-4606
NSN 5920-01-448-4310
NSN 5895-01-428-3317
NSN 5925-00-597-1558
NSN 5920-00-320-7800
NSN 5990-01-432-4984