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 6145-00-003-4177
NSN 6620-01-564-9870
NSN 5915-01-601-9377
NSN 7035-01-400-3666
NSN 6220-01-558-3212
NSN 5855-01-364-8193
NSN 6145-00-033-2997
NSN 5999-01-316-9039
NSN 5910-01-450-0955
NSN 5925-01-412-2934
NSN 7035-00-337-8745
NSN 2925-01-608-1888