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 5990-01-633-9503
NSN 5855-01-157-7186
NSN 4140-00-948-3663
NSN 5998-00-729-5614
NSN 5945-00-821-4330
NSN 5910-01-369-6252
NSN 5950-00-382-7741
NSN 5835-01-623-3328
NSN 5935-00-689-3499
NSN 6110-01-027-6180
NSN 6240-01-123-9040
NSN 5950-01-381-0256