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 5990-00-789-1333
NSN 6135-00-702-2772
NSN 5998-01-102-7928
NSN 5915-00-700-5728
NSN 5930-00-733-2578
NSN 6610-00-614-7943
NSN 4140-00-243-6664
NSN 6320-01-215-2284
NSN 6135-01-367-6203
NSN 6645-01-252-8870
NSN 5925-00-837-8964
NSN 6105-01-017-2748