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 6110-00-205-1778
NSN 6320-01-409-1388
NSN 5975-01-171-7111
NSN 6610-00-990-9825
NSN 7035-00-849-5526
NSN 6130-01-121-0962
NSN 5990-00-466-2952
NSN 5998-01-422-7110
NSN 6135-01-428-7490
NSN 5855-00-862-3345
NSN 5935-01-213-9112
NSN 6220-01-261-2488