This mini 10W aquarium heater features a digital display and intelligent temperature control for precise and constant heating. It also has an external temperature controller for safe and easy adjustments. Its small size makes it easy to hide and saves space, while the memory function ensures it retains its last setting in case of power loss. Suitable for both fresh and marine water, it can be used for not only fish tanks, but also turtles, pet fountains, and plant seedlings. Features: 1. Mini Size: The super mini size perfectly solves the headache of the fish keepers on the traditional heaters. Takes up less space, easy to hide, but in full power. 2. Precise and Constant Temperature: An intelligent IC chip controls the heaters temperature. The fish heater will automatically start heating when the water temperature is lower than the set values and stop heating when the water temperature reaches the target. 3. External Temperature Controller: Adjust the temperature from 18-34C, this fish tank heater is adjusted by an external controller, which you can mount on the outside edge of the tank. Its convenient and safe for you to set the temperature, No need to put your hands in the water to adjust the aquarium heater temperature. 4. Memory Function: The last setting is stored in the thermostat. In case of a power cut, when the power recovers, the heater will follow the last setting. 5. Multiple Use: This heater can be used for both fresh and marine water. It can be not only used as an aquarium heater, but can also work for turtles, pet fountains, and plant seedling. Specification: Material: Quartzs Glass Product Color: Black Product Size: 15.5 x 8.5 x 5.5cm Product Weight: 119g Power: 10W Temperature Control Range: 18-34C Control Accuracy: 0.5 Package Included: 1 x Small Aquarium Heater