Easy to read LCD(26.5mm x 13.5mm) temperature with suction cup for secure convenient placement Submerge probe into fish tank to measure water temperature (Submerge probe only, do not submerge thermometer in water, only the sensor is waterproof) Digital Thermometer with external thermistor with 3 ft insulated wire, can switch between C and F Accurate Temperature reading to within 0.1 degree, switch temperature measuring range: -50C ~ +70C and operating temperature -10C~+50C Enjoy convenient monitoring of parameters essential to Fish and reptile health, ideal for Aquarium or any place you want to monitor the temperature. - Temperature measuring range: -50C ~ +70C - Resolution: 0.1C - Accuracy: +/- 1C - Power: DC 1.5V button battery LR44 - Input: 1NTC sensor - Sensor wire: Approx. 3.28 feet - Ambient requirements temperature: -10~60C; humidity: 20~85% (No condensate) How to operate our aquarium thermometer? 1. Open the battery cover and insert battery with (+) positive pole up, then screw up the cover. The LCD will display the current room temperature. 2. Using the suction cups provided to attach the thermometer to the outside of the aquarium, and submerge the sensor probe into water in the aquarium. Don't submerge the thermometer, only the sensor probe is waterproof! 3. To preserve battery life press the PWR button for three seconds to power off or remove the battery. To power on press the PWR button. 4. If the LCD displays HC, means temperature is higher than 70C. If displaying LC, means temperature is lower than -50C. Package Contents: 1 x Battery 1 x Digital Thermometer