Intelligent Digital Thermometer Hygrometer: The mini digital hygrometer has 3 symbols. A smiley face is displayed when the humidity level is between 30% and 60%. It displays water droplets when humidity is below 30% or above 60%, indicating dryness or humidity, so you can adjust your humidifier or dehumidifier accordingly and always live in a pleasant environment. Temperature monitoring: -20C ~ 70C. Temperature measurement accuracy: 1C, temperature resolution: 0.1 (C). C/F selection at the touch of a button, indoor thermometer measurement data updates every 10 seconds. Indoor Hygrometer: 10% RH~99% RH. Humidity resolution: 1 (RH), humidity measurement deviation accuracy: 5% RH. (The difference of 1C/% RH between two thermometers may exist, but it is normal). Super Portable: This thermometer-hygrometer (7.9 x 5.8 x 2.2 cm, weight 56 g) is small and light enough to be carried around without taking up too much space. The thermometer-hygrometer can be placed on a desk, mounted on a wall or on a magnet, and its sleek design makes it a beautiful addition to any room. Wide Range of Applications: the mini Digital liquid crystal thermometer-hygrometer is popular and inexpensive. The thermometer/hygrometer is suitable for use in apartments, bathrooms, children's rooms, warehouses, cellars, greenhouses, offices, farms, warehouses, etc. The thermometer works with 2 x 3AAA-7 (Not included) and has a standby time of up to one year.