Isotemp Stainless Steel Marine Water Heaters are specifically designed for use in the demanding marine environment. Isotemp features a brushed stainless steel cover and a 316-grade stainless steel inner tank that is backed by a 5-year limited warranty against leakage due to corrosion or manufacturing defect.Isotemp Stainless Steel Water Heaters achieve the highest capacity by optimizing the position of the engine water heat exchanger as well as the electrical immersion heater. These are positioned in the lowest part of the tank where the water is coldest in order to ensure an equal heating of all the water in the tank. The water inlets and outlets are specially designed to minimize the mixture of cold and hot water.All Isotemp tanks come standard with the innovative Isotemp Temperature Control Safety Mixing Valve, which protects users from scalding hot water. Water heated with engine heat exchangers can be heated to 190 degrees or more, which could scald those unfamiliar with boat water heaters. Water will also be heated to 160+ degrees with just the electric heating element alone. By adjusting the Isotemp thermostat-controlled mixing valve, the boats water is mixed with the hot water to deliver the temperature you want at the faucet. This mixing action also speeds up recovery time and extends the volume of hot water you get from a smaller tank.115V/750W20 gallon (75 liter)Safety mixing valve Dual heat exchanger5-year limited warranty