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 6135-01-595-4779
NSN 5920-01-624-8589
NSN 5925-01-044-5508
NSN 5999-01-624-7455
NSN 6110-01-393-6992
NSN 5910-00-682-0746
NSN 6240-00-942-5018
NSN 5998-00-816-9752
NSN 5895-00-633-7623
NSN 6650-01-370-5265
NSN 5915-00-892-9215
NSN 2925-01-443-4216