Estone Aquarium Fish Decal Tank Digital Thermometer Sticker Big,easy to read digits that tells you, unmistakenly what the temperature is in both Celsius and Fahrenheit degrees. Unlike traditional thermometer that takes forever to figure out where that little red bar in the tube sits. Temperature is accurate up to 1 degree in Celsius and 2 degrees in Fahrenheit Size is just right for any Aquarium Easy to install, just peel off the back of the sticker and the transparent protective film at the front and stick it on the outside wall of the aquarium, that is it! No battery and suction cup to worry about Good quality with low price. Size:12.9cmx1.7cm/5.08"x0.67"