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 5925-00-883-1171
NSN 6685-01-411-5969
NSN 5950-01-507-2145
NSN 5990-01-578-1499
NSN 5925-01-466-0676
NSN 5925-00-144-0482
NSN 5990-00-874-3036
NSN 6110-00-614-9218
NSN 6105-00-601-6869
NSN 5996-01-119-6535
NSN 2925-01-058-1718
NSN 5895-01-363-1035