Originally Posted by atikovi
I can't understand why they don't sell a concentrate that you mix with water instead of the gallon jugs of the stuff which I assume is just 98% water anyway and 2% chemicals. Just shipping it is probably half the retail cost of the fluid in the stores. Say, a quart of concentrate for $10 that makes 5 to 10 gallons of fluid, and you can adjust the freeze point to your local weather, just like you do with antifreeze. Each capful lowers the freezing point 10 degrees so 4 capfuls and you're good to at least 0F with a good margin for error.
The Rain-X stuff is a concentrate that "legally" has to be mixed at no greater than 2oz/gallon(1:64 ratio) for areas with VOC restrictions(CARB Type B[but CA does allow for stronger mixtures in the winter], Texas and other states that follow OTC regulations). CA does allow for the sale of washer fluid concentrate.
Einszett and 303 are available and I feel those are much better cleaners.