Aqua Medic T-meter II is a external aquarium thermometer for fixing on the aquarium glass (outside) or in the cabinet.+ compact design and easy operation+ large LCD display showing the water temperature+ separate power button for turning off the display (power saving mode)+ external temperature sensor, can be hidden in the aquarium+ selectable temperature unit:C orF+ easy fixing on the aquarium glass by suction cups+ can also be fixed to the cabinettechnical Data Aqua Medic T-meter IIMeasuring range: +5 to +45C (+41 to +113F)Measuring steps: 0.1C / 0.1FMeasuring accuracy:1C (2F)Power supply: 1.5 V (AG13/LR44)Attention: Do not immerse the display unit in water. Only the sensor is waterproof.Display = HC - the temperature is above the measuring rangeDisplay = LC - the temperature is below the measuring range