SK-II Hong Kong & Taiwan, page-160

I'd say the wand will work on any number of SKII formulations (and any other brand) insofar as it is tuned to a molecule and not a "brand". So if the wand/device is tuned to "Molecule A" and that is used by 10 products then it would work on those. If the Molecule was proprietary (or unique to only one product) , yes it would only work there. It would probably work for other molecules as well, if they had the same/similar magnetic signature. I'm not concerned about the physics too much, its the marketing that will make the money in the long run