Features: The outer casing is made-of aluminum-alloy, compact-size, strong and durable. Indoor and outdoor mini round aluminum-alloy hygrometer thermometer. Suitable for houses, offices, workshops, schools, shopping malls, warehouses-etc. Large disc with bold-numbers, large metal wall thermometer with hygrometer. with the 10cm diameter disc display,easy to read the temperature and humidity value from distance. Environmental-protection,this wall thermometer implementing concept of green which without batteries, energy saving, environmental-protection. it use different bending degrees of temperature sensitive metals in different temperature environment to realize the display of temperature. Exquisite-design, can display or hangs,metal discdesigned to show more-elegance. large instrument display for easy reading from a-distance. Specifications: Material:Metal Diameter: Approx.100mm/3.93inch Thickness: Approx.30mm/1.18inch Style: thermometer Style: hygrometer Temperature range: 0-120℃ Humidity range: 0-100%RH Measurement accuracy: temperature ≤ 2℃; Humidity ≤ 7% Usage: wall hanging Battery storage type: no battery is needed. Product material: alloy-aluminum Scope of application: this product is widely used in archives, saunas, bathrooms, steaming room, hot-spring room, offices, Hotels, restaurants, schools, factories, conference room, shopping malls, pharmacies, hospitals, laboratory machines. Field, theater, warm and humid nursery, courtyard-home Package Includes: 1x Hygrometer Thermometer note: ①.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. ②.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.