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 5990-01-345-1468
NSN 6685-00-596-8765
NSN 2925-01-143-1874
NSN 6220-01-374-3147
NSN 5999-01-505-7896
NSN 6135-01-517-6060
NSN 5915-01-167-8506
NSN 6105-00-084-3055
NSN 5920-01-487-5516
NSN 5999-00-644-9767
NSN 6110-01-231-7360
NSN 5910-01-563-8558