Free warm water thanks to eco-friendly solar power. Even on cloudy days, the water in the 20-litre bag heats up to 40 °C. The newly developed version is black and blank on the back, which guarantees superfast heating. This prevents the proliferation of algae as no light can penetrate. Can be used horizontally or hanging up. Two valves, one on the bag for safe transportation, the other one on the shower head for a convenient handling. Phthalate-free.