Features: Versatile design: Use calibrated sensing modules to reduce deviations and improve accuracy, with temperature units selection for fast switching. Widely applicable to temperature and humidity measurement of room, subway, library, commercial center, communication centers and other equipment. Portable and convenient handheld size: The meter is small and portable, and the white backlight LCD display can be used in dark environments. High-precision design: Humidity and temperature are designed with high-precision humidity and temperature sensors for high accuracy, fast response and stable readings. More functions: Data hold, MAX/MIN, enable/disable auto power off, over range indication, low battery indication. Specification: Humidity Measuring Range: 0~100%RH Range Accuarcy Resolution 45~75%RH ±3.0 %RH 0.1 Other ±4.5 %RH Temperature Range Accuarcy Resolution -20℃~70℃ ±1.0℃ 0.1 -4℉~158℉ ±1.8℉ Dew Point Temp. -20℃~70℃ ±1.5℃ 0.1 -4℉~158℉ ±2.7℉ Accuracy is bades on environment condition of 25 ℃, 40%-100%RH Wet Bulb Temp. -20℃~70℃ ±1.5℃ 0.1 -4℉~158℉ ±2.7℉ Data Update 0.5s Auto Power Off 15min Operqating Environment -20℃~60℃/-4℉~140℉, 10%RH~90%RH Storage Environment -20℃~60℃/-4℉~140℉, 10%RH~75%RH Power Supply 3 x 1.5V AAA batteries (NOT included) Battery Life >50 hours Dimensions 168x55.6x30.8mm / 6.6x2.2x1.2in Weight 139g (approx.) Package List: 1 * Temperature Humidity Meter 1 * User Manual