I bought a clay magic clay bar kit that came with some clay lube in a spray bottle. It says on the bottle that not only can it be used as a clay lube, but can also be used to deminish water spots and smudges from the paints surface. I thought to myself, "will this take off water spots from my windows?" Why yes, it will! Works like a charm. This stuff sorta works like a wax. You spray it on the surface to be cleaned, wipe the area with a 100% cotton towel or rag, it will haze like a wax, then use a dry rag to buff it spotless! Easy as that. Try it. It really works.