Zacro Digital Thermometer Features An Easy To Read Digital Display With Temperature In Either Fahrenheit Or Celsius Depending On Your Choice The Thermometer Is Accurate Enough To Create Readings Within 1 Degree Looking For A Thermometer For Your Fish Tank Our Digital Thermometer Is A Good Choice For You Strong>Operation: Strong> 1 Open The Battery Cover And Insert Battery With (+) Positive Side Up The Lcd Will Now Display The Current Room Temperature 2 Attach The Display Unit To The Outside Of The Tank Using The Suction Cups And Submerge The Probe Into The Water In The Tank 3 Press And Hold The Power (Pwr) Button To Turn On Hold The Power Button For 3 Seconds To Turn Off Strong>Technical Details: Strong> Size: 2 X 125 Color: Black Batteries: Lr44 (Included) Strong>Package Contents: Strong> 2 X Lr44 Battery 2 X Digital Thermometer 2 X Probe Strong>After Service: Strong> Donat Hesitate To Contact Us If You Have Any Question When You Use It, All The Zacro Products Include A 24-Month Warranty, We Will Try Our Best To Meet Your Satisfaction