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 6240-00-859-5936
NSN 5910-01-254-2799
NSN 5990-01-474-3477
NSN 5996-01-453-2464
NSN 5935-00-765-1238
NSN 5960-00-799-4056
NSN 6150-01-293-2459
NSN 6685-01-451-4796
NSN 6240-01-532-5978
NSN 5998-01-265-1364
NSN 6645-00-965-1488
NSN 5935-00-375-5189