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 5965-00-548-7119
NSN 6240-00-799-1528
NSN 5960-01-491-9916
NSN 5999-01-459-9082
NSN 6240-00-715-5118
NSN 4140-00-484-4040
NSN 6610-00-448-1264
NSN 5835-00-861-6066
NSN 7035-00-153-3826
NSN 5915-01-350-2407
NSN 5965-00-583-4865
NSN 5905-00-916-9066