This meter is for testing the environmental temperature and relative humidity which is the percentage expressed by %RH signal of the absolute content in air with the saturated steam content in same temp, pressure and volume air. The ways of using is extensive, for instance, hyperpure metal smelting, textile process, papermaking, printing and dyeing, and food storage, weather forecasting, the temp/humidity in air or industrial process can be tested or controlled by the meter.Features:This is digital thermometer hygrometer is a new type of digital temperature and humidity meter, which designed to combine the functions of humidity meter, temperature meter and time display.LCD display with backlight with high accuracy sensor, LCD brighter in the darker places, and has energy saving auto backlight off function.Dual display humidity and temperature with accurate measuring, easy to watch.MAX / MIN / data hold and data storage functions, high accuracy & fast response.Low battery indication, auto power off, energy saving.Specifications:Material: ABS plasticAmbient Temperature:Range: -20~60C (-4~140F)Precision: 3C / 0.5FResolution: 0.1C / 0.1FRelative Humidity:Range: 0~100%RHAccuracy: 3.0%RHResolution: 0.1%RHTemperature Response Time: >2s(depends on the heat exchanging type)Humidity Response Time: 8s(the time of humidity going to the order quantity, 25C, 1m/s air flowing)Screen Refreshing Time: 500msMax/Min Temp/Humidity Alarm: YesMax/Min Temp/Humidity Measurement: YesTime Display: YesData Hold: YesData Storage: 100 groupsAuto Backlight off: 10 minutesAuto Power-off: 30 minutesPower Supply: 3 * 1.5V AAA battery (NOT included)Item Size: Approx. 188 * 64 * 27mm / 7.41 * 2.52 * 1.07inItem Weight: Approx. 126g / 4.47ozPackage Weight: Approx. Approx. 288g / 10.18ozPackage Size: Approx. 23.3 * 18 * 5.5cm / 9.18 * 7.09 * 2.17inPackage List:1 * Digital Thermo-Hygrometer1 * User Manual (English)