Enough to Use: there are 1 pieces of digital aquarium thermometers in the package, to meet your use and replacement; Each aquarium temperature gauge is approx. 1.69 x 1.69 x 0.47 inches/ 4.3 x 4.3 x 1.2 cm, which is small and compact, won't take up much space when it is stuck to a fish tank High Precision Display: the temperature sensor of this aquarium thermometer digital is accurate and sensitive, which can accurately display the temperature in the fish tank; The temperature measurement range is wide, and the reading range is 32~140, which can meet the measurement needs of various water temperatures LED Digital Display: the fish tank thermometer adopts LED digital display, which can display the temperature in the aquarium, the display value is large, the color is saturated, and the temperature value is clear and easy to read even in the dark Easy to Use: the aquarium digital thermometer has a transparent double sided adhesive on the back, you just need to peel off the tape and stick on the outer wall of the fish tank; Our thermometer adopts a highly accurate sensor, so it can accurately measure the temperature without placing it in the water, no messy wires, which can protect your fish from electrocution or accidental ingestion Long lasting Battery: this LED aquarium thermometer has a built in 3V ultra low power battery, which is energy saving and long lasting, and the battery life is up to 5 years; When the battery runs out of power, you can replace the battery by yourself