Marina Digital Thermometer - an easier and more accurate way to monitor the temperature in your aquariumMarina ThermoSensor Probe is an aquarium thermometer with an easy-to-read digital display. The thermometer monitors and displays the temperature inside and outside the aquarium in both Celsius and Fahrenheit. The unit comes with a Velcro mount for easy installation anywhere on the aquarium. Battery included. Temperature range: -50 C to +70 C (-58 F to +158 F)