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 6130-00-589-9948
NSN 5990-00-345-8967
NSN 7035-00-059-7970
NSN 2925-01-556-0333
NSN 6150-01-389-6762
NSN 6150-01-167-8315
NSN 6610-00-270-9974
NSN 5910-00-470-2772
NSN 6135-01-276-5402
NSN 6240-00-153-8929
NSN 5855-01-575-0061
NSN 5920-01-342-3681