Brug's® AcidWash – Low pH Pre-Wash Foam

Works great will remove water spots from glass, Im not sure about if its old and etched as mine was not that bad but water spots that would not wash off disappeared. use foam canon and mix per instructions.

Some of my first use with the acid. I mixed as directed, and it removed water spots from all the glass, awesome and eliminated that job to hand polish all the windows. Although it removed some from paint, it was only the condition of the paint that called for me to buff them out. I would assume if i used it sooner it would remove them from paint as well.