Top secret. (I think it sez this in the instructions) :doh:
Zymol is one of the best high end waxes available. It can be a bit trickey to get down and rubbed off, especially if it's a bit warm or muggy out. It's very thick and will clod up if your greedy or sloppy with it. To get a proper "haze", thats easy to rub off; I use a bit of warm water in a small container to thin it, and rinse in between sections in a full bucket of water. The shine is just as good as ever and it keeps the Karate Kid syndrome to a minimum. (wax on wax off). This way you conserve your sweat equity as well as stretching the bottle into the years. Zymol isnt cheap. Most of what you apply gets duffed off as waste anyway.
Mother's
Zymol is not not my first choice for scale models or general use, though. I prefer a lighter product like Mothers or MeGuiars that cuts off easy with a flick of the linen, and a minimum of effort. They are never going to see weather or pounding UV. Sometimes less is more.