The hygger Fully Submersible 800 W Aquarium Heater is a high-quality, durable heater that is perfect for marine and freshwater environments. With its easy-to-use LED digital screen, you can easily set the temperature in your environment to a comfortable level. The double tubes heating element provides fast, steady, and more evenly distributed heat. The PC plastic guard protects your fish from getting burned by the heater. The running-dry shut off protection prevents the heater from accidentally turning off. And the overheating protection turns off the heater when the water temperature reaches 95F.