Fluctuations in temperature cause changes to the water’s specific gravity, ability to hold oxygen and causes stress to fish, often leading to disease. A consistent temperature is a key element of stability, and stability is a cornerstone of the successful marine aquarium. D-58 Digital Display Controller provides a remote sensing thermometer and digitally precise temperature control for the Heater. Know in a single glance the thermostat setting and the aquarium temperature with two bright independent LED displays on each Controller. Finnex Heating Elements are constructed from titanium and use premium components to provide precise and reliable heating when paired with our D-58 Heater Controller. D-58 Controller Specifications: - Temperature control range: 0°C to 40°C (32°F to 104°F) - Temperature measurement range: 0°C to 70°C (32°F to 158°F) - Precision: ±1°C (±1.8°F) - Voltage:115 volt, HZ: 60 HZ, Amps: 10A - Max. Load: 800 watt - Temperature display: 3 digit (display down to one place of decimal) - Setting temperature display: 3 digit (not display down to one place of decimal) - Sensor (probe) cord length: 6 feet - Indicator light: heater ON / OFF (ON is red light) - Conversion of reading in °C or °F: Green light - Resolution for water temp: 0.1°C / 0.1°F - Resolution for set temp: 1°C / 1°F