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 5910-00-167-1220
NSN 5960-01-173-7956
NSN 5990-00-067-6791
NSN 6620-01-362-4276
NSN 5855-01-648-2674
NSN 5925-01-660-6619
NSN 6610-00-498-3257
NSN 6105-01-421-1493
NSN 6220-01-554-0639
NSN 5835-00-257-2852
NSN 6105-00-915-2657
NSN 5935-00-398-1584