Large Numbers Easy to Read: Large numbers, clear lenses, and temperature and humidity can be seen at a glance from a distance. Different color scales indicated for reference. Wall holes on the back for hanging for easy reading Auto Calibration: This indoor outdoor thermometer wireless comes with a -manufactured thermometer coil to accurate readings, a built-in mechanical movement for real-time sensing, and the thermometer hygrometer automatically calibrates within 2 hours. So you don't need calibration and no batteries Temperature and Humidity Measurement Range: The 12inch outdoor weather thermometer decorative accurately measures temperatures from -60 to 140℉ (-50 to 60℃ ) and humidity ranges from 20% to 90% . Keep your home or garden in good condition by controlling temperature and humidity with outdoor temperature thermometer Stainless Steel Enclosure: The decorative outdoor thermometer is made of stainless steel with glass lens, black pointers, this large outdoor thermometer hygrometer is strong and , you can use it for a long time without damage. High-quality glass lenses also 't turn yellow Indoor Outdoor Thermometer Hygrometer: Large wall-mounted thermometer and hygrometer can be placed outdoors or indoors, such as: gardens, courtyards, balconies, greenhouses, warehouses, factories, schools, offices, hotels, kitchens, baby rooms, laboratories, etc. Exquisite silver thin edge shell can decorate your room very well., Manufacturer: CTRLZS