I bought the cleaner for my Kärcher window cleaner. One does not need much of it for a filling of the spray bottle. I'm surprised how well you can clean windows with as little liquid. With Sidolin that would not work out. Since I only bimonthly brush my window and you really need only a sip of cleaning fluid for clean windows, to get relatively long way with the glass cleaner. Considering the comfort of the Kärcher system over a traditional window cleaning I give the money from you.