The Eheim thermocontrol e is a top of the line, fully submersible aquarium heater designed for both freshwater and saltwater environments. The heater itself takes on the classic "hang in the water" design, but elevates its functionality with incredibly precise temperature adjustments between 20 C and 32 C, accuracy within 0.5 C and dry-running protection to offer unmatched safety and control. The unit has been constructed with a state-of-the-art glass jacket that increases the heating surface and acts like a heat shield, ensuring optimum heat emission and uniform distribution around the tank. For greater ease of use, this ultra modern electronic thermal device requires zero readjustment for accurate results, a convenient 170 cm long plug in cable, a double suction cup holder to securely place the heater anywhere in the tank and a easily visible control lamp that indicates red for "heating up" and green for "temperature reached". The heater has an output of 125 watts and is ideal for aquariums between 40 and 53 gallons in size.