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 5930-01-534-1951
NSN 5950-01-478-6049
NSN 7035-01-583-0497
NSN 7035-01-574-6363
NSN 7035-01-222-2534
NSN 6320-00-270-8222
NSN 5935-00-285-2767
NSN 5925-00-689-1453
NSN 6145-01-371-2404
NSN 6610-00-825-5774
NSN 6320-01-624-0193
NSN 5975-01-463-9869