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 5930-00-209-6956
NSN 5965-00-067-7393
NSN 5935-01-369-6479
NSN 6150-00-023-4968
NSN 5925-00-993-4603
NSN 6610-01-300-0968
NSN 5960-01-500-6615
NSN 6135-01-495-0933
NSN 5910-00-758-1250
NSN 5905-01-393-0545
NSN 6220-00-901-6318
NSN 6240-01-396-5639