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 5998-00-864-8336
NSN 6650-01-205-8578
NSN 5855-01-225-5855
NSN 5925-01-462-0068
NSN 6220-01-265-8650
NSN 6220-01-333-6084
NSN 6685-00-806-9345
NSN 6135-01-389-8289
NSN 5998-00-712-8963
NSN 5920-01-042-9351
NSN 5999-00-039-7792
NSN 6240-00-151-5382