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 5998-01-428-9545
NSN 6610-01-224-6956
NSN 6240-01-212-2850
NSN 5985-01-212-2950
NSN 5985-00-205-9568
NSN 5930-01-515-7840
NSN 5855-00-832-9341
NSN 6685-00-688-5154
NSN 5996-00-989-7764
NSN 5855-01-147-4785
NSN 6130-01-277-1594
NSN 6135-00-221-4720