An essential tool for experimental measurement of air relative humidity. It is widely used in grain storage, greenhouse cultivation, sericulture, tobacco harvesting and drying, weather observation, food processing, etc. Features: Function: Analog thermometer and hygrometer measures temperature and humidity Easy to read: Bold and easy-to-read numbers, you can read the measuring data easily, the numbers are fade resistant High grade material: High-impact, durable plastic construction, reliable material ensures durability. Wide application: Great for basement, garage,barn, greenhouse, labs, nursery, room and more. No battery needed: The thermometer is mechanical and not electronic, there is not batteries to run dead, money saving and time saving for you. Specification Temperature measurement range: -1050 / -20~50() Measurement error: 2() Accuracy class: 1.5 Humidity measurement range: 0-100%RH Measurement accuracy :1 % Red size: 257*92*25mm Blue size: 300*105*30mm Instructions for use 1. The wet and dry thermometer should be hung in a ventilated place to keep the ribbon and pot of water clean. 2. Pour clean water into the kettle below and immerse the yarn into the kettle before use. 3. The humidity checked by this dry and wet thermometer is calculated in degrees Celsius (). If the second meter is at the same temperature, it means that the water vapor in the air has reached the saturation point. 4. The rotary calculation plate installed at the lower end of the wet and dry thermometer is a dry and humidity comparison table to check the humidity in the air. 5. How to use: According to the rotation calculation of the wet and dry meter thermometer, make the dry bulb temperature scale line up with the wet bulb temperature scale. The reading number indicated by the arrow direction below is the relative humidity. Package included: 1 * Dryness meter hygrometer thermometer