Over the years cleaning in low sun has been a problem for some with getting smears! windows looked fine from outside but when you looked from the inside windows looked smeared, well for the past 2 weeks i have been using 2 capfulls of this into my water! http://flashcleaner.co.uk/en_UK/apc-cleanshineliquid-crisplemon.do And i can say it is absolutely brillant to add to your wash water! i have been absolutely flying these past 2 weeks with this added to my water no streaks smears nothing even with the sun on the glass this still cleans brillant added to your soap mix! leaves a really good shine on the glass as well, I must say am well impressed with this added to my mix and so will you be! Try it lads you wont be disappointed!