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 7035-01-034-6183
NSN 5950-00-258-6776
NSN 5960-01-229-6324
NSN 5915-00-217-6517
NSN 5915-00-078-9574
NSN 6135-01-419-5574
NSN 6105-00-527-8571
NSN 6110-00-113-1415
NSN 6620-01-454-8926
NSN 5920-00-384-8926
NSN 6150-01-539-3197
NSN 6240-00-526-0243