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 5925-00-853-6198
NSN 5998-01-112-6061
NSN 6650-00-373-9220
NSN 5915-01-263-6412
NSN 5965-00-255-3889
NSN 5965-01-658-1296
NSN 5965-01-360-0454
NSN 5895-01-648-4594
NSN 5895-00-011-7880
NSN 5905-00-597-8280
NSN 6645-00-300-0401
NSN 5930-00-850-7284