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 5996-00-079-1268
NSN 5996-00-570-5187
NSN 5996-01-294-2679
NSN 6610-00-080-2985
NSN 5855-01-354-7291
NSN 4140-01-593-8951
NSN 6105-00-232-8291
NSN 6150-00-420-2407
NSN 6240-01-229-5712
NSN 5835-01-624-5666
NSN 6110-00-610-9119
NSN 5975-00-755-3703