The first design and energy efficient radiators in the market. Low-H2O stands for Low- water content and mass. Low-H2O radiators contain only 10% of the water content from a panel radiator with identical output. Hereby the inertia is minimal so these radiators can react immediately on external factors, allowing you to benefit from free heat sources such as sunshine, cooking, ironing etc. Low-H2O also stands for Low- water temperatures: these radiators are actually designed to operate on a supply water temperature starting from 110°F (with optional DBE even from 90°F).