Double Safety Protection: According to customer demand, we have upgraded the electric heater with built-in temperature control and fuse, automatically stop heating and maintain the temperature when the water temperature reaches 167?. The fuse can cut off the power to avoid fire, providing double safety protection and enjoying a comfortable soak at home. Heaters are NOT suitable for liquid heating in standard drinking cups? due to critical operational constraints and safety considerations? Fast Heating: 1500W high power fast immersion water heater can heat 5 gallons of ROOM TEMPERATURE WATER in minutes, saving energy and money. If you want to heat up for a shorter time, you can use 2 water heaters at the same time, but be careful NOT to use them on the SAME OUTLET. The heating time will be little longer in cold weather. We recommend a maximum use time of 3 hours. And this immersion heater is ONLY for WATER HEATING. Simple Operation: Immersion water heater is easy to use, make sure the immersion water heater is fully immersed in water and the water level is sufficient before powering it on. Keep watching and keep hands off. Once water is hot enough or boiling, unplug the heater and wait a few seconds before removing it from the water. Anti-scalding Corrosion Resistance: The pool heater with corrosion resistance stainless steel protective guard can effectively prevent the heating element from directly contacting the people or animals, both sides are fixed with mechanical and AB glue, which has strong sealing and is safer. Strong corrosion resistance, for you to solve the trouble of no hot water. Widely Use: The heater can be used for inflatable swimming pool, bucket, washbasin, bathtub, washbasin, construction, car washing, etc. The immersion heater is lightweight and small, easy to carry when you go camping. As standby water heater of combined boiler.