Meet the sunlabs sk-v4 solar water heater sun kettle. New and improved design over other brands and models. Boil water to 212 degrees f using just sunlight. Large 16.9 fluid oz vacuum heater tube. Stainless steel components. Vertical adjustment rod for increased efficiency and time required to bring water to boil. Newly updated heater tube with increased efficiency. Built-in removable thermometer (100% analog – no batteries required). Easily add water or pour without removing lid. No burn soft touch handle. Wide handle design for increased stability.