Thanks for the replies. I'm not worried about it breaking; it's stranded, not solid core, and the sheath is pretty tough. This is the stuff that is used for headphones and such, so flexibility is not a problem. There is no flexing or strain expected in this installation; it's going from the rack leg to the light, that's it. No chance to go 2 conductor for this short 1 foot stretch, I absolutely need 3 conductors.