Use steps First press the PWR button on the aquarium thermometer; Then put the sensor probe in the water; The attached suction cup can paste the LCD screen to the side of the aquarium. Easy to read You can easily read the water temperature with the LCD screen of the aquarium thermometer . The temperature unit can be switched between C and F with the button. Measuring range The measurement range of the thermometer for aquarium is -50 C ~ + 70 C / -58 F ~ 158 F, the precision is +/- 1 degree Celsius. Dimensions: 58 38 15 mm. Power supply: LR44 battery (included). wide application The aquarium thermometer is suitable for aquariums, aquariums, reptile boxes, incubators, refrigerators, cigar houses, etc. It can protect reptiles, fish and small animals dangerous temperatures. The package includes You get 2 Aquarium thermometers, each with 1 LR44, a 1.5 V button battery and 2 suction cups. Length of the cable of the probe: 1 meter. Note: Do not put the thermometer in the water, only the