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 7035-01-353-6861
NSN 6105-01-495-0623
NSN 5925-01-521-6817
NSN 5999-01-223-0572
NSN 5855-00-688-9954
NSN 6150-01-562-4633
NSN 5925-01-050-8195
NSN 4140-01-564-4927
NSN 5930-01-536-4141
NSN 6135-01-074-2529
NSN 5905-01-459-9969
NSN 5999-00-551-9434