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 sensor of the probe is waterproof.SpecificationMeasuring range: -50 C to + 70 C (-58 F at + 158 F)Operating temperature: -10 C to + 70 C (-50 F to + 140 F)Maximum accuracy: 0.1 CError margin: +/- 1 CBattery: LR44 button battery (included)Cable length of the sensor probe: approx. 3 feet (1 meter)NotePress the power button (PWR) and hold down to turn on. Hold down the power button for 3 seconds to turn off.when the temperature is greater than 70 C or less than -50 C, "H C" or "L C" appears to The screen.The main display unit of the thermometer must be kept away from the water because it is not waterproof.The package includes2 x Aquarium thermometers2 LR44 button batteries4 x Suction supportsLCD screen displayThe LCD screen easily reads the temperature of the water. The button can be used to switch between C and F.LR44 button batteryThe product is equipped with a LR44 button battery for power supply, which is durable and replaceable, and can be used for a long time.2 suction cupsOne is a fixed thermometer and the other is a fixed probe. Clean the surface of the suction cup to get the best adsorption effect.Waterproof probeThe high quality probe can operate normally under water without corrosion or crack.