Rust and Corrosion Resistance: This aquarium heater is made of high quality stainless steel material, which is sturdy, rust and corrosion resistant. Double-Layer Waterproof Protection Design—This aquarium heater adopts double-layer waterproof protection and fully submersible design, can accurately maintain the set temperature and not short circuit. > Thermostatic Design: This aquarium heater adopts double-metal silver-plated contact temperature control and internal fixed temperature adjustment process, which has strong temperature sensitivity and small temperature error . Wide temperature range and large depth: This aquarium heater can be adjusted from 18 to 34 degrees. Its maximum immersible depth is 120cm and is suitable for using in fresh water. With strong suction cup: This aquarium heater with strong suction cup can fix the heater on the tank firmly and stay stable for a long time.