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 6610-01-423-7481
NSN 5925-01-578-6869
NSN 6645-00-149-1100
NSN 5895-00-974-9586
NSN 5925-01-090-8657
NSN 5990-01-633-9503
NSN 5998-01-332-1658
NSN 5999-01-649-2810
NSN 5990-00-222-9899
NSN 5915-01-344-0942
NSN 6320-01-335-8336
NSN 5945-00-244-0557