After having my windows cleaned I noticed that there were white spots everywhere. I called PureTek and they explained there was some issue with their equipment and it was leaving a mineral deposit behind. My windows were covered in white spots! They were apologetic and promised to re-clean them within the next few days. That was in April. 3 months later and 50 plus phone calls later....I have been promised more than a dozen times that the windows would be re-cleaned, and this has never happened. If PureTek H20 comes knocking on your door, take my advice. Don't answer it.