Marina LCD Digital Aquarium Thermometer
Liquid Crystal Stick On Digital Thermometer. Accurate and simple to read, sticks on outside glass. removable. Reads 18-30 degrees Celsius, or 64-86 degrees Fahranheit. Green indicates the correct temperature. If green is not visible, the correct temperature is halfway between tan and blue. Keep away from direct sunlight. Dimensions .75" X 1.75"