A waterless wash works when the car is only lightly dirty: the lubricants help lift dust and light dirt into the towel. ECH2O adds a high gloss SiO2 component, so the finish suits a coated car.
Because it is a concentrate, one bottle covers several jobs. CarPro US also lists rinseless wash and clay lubricant mixes.
CarPro built it on two years of research, around a SiO2 hybrid framework and an eco-friendly organic lubricant, and CarPro US says 500ml makes up to about 2 gallons of waterless spray at 1:15.