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 6110-01-380-1419
NSN 6135-01-151-2705
NSN 5935-00-981-5155
NSN 6610-00-931-3656
NSN 5930-01-309-4676
NSN 6130-01-111-9865
NSN 5910-01-007-9298
NSN 6220-00-737-4162
NSN 6145-00-635-9957
NSN 6135-01-056-4609
NSN 6240-00-295-1184
NSN 4140-01-270-6599