Wall-Mounted Carbon Dioxide Meter, Carbon Dioxide Concentration 380 to 2000 ppm, Temp. Range 14 to 140 Degrees F, Relative Humidity Range 0 to 85 Percent, Dew Point Range -4 to 139.8 Degrees F, Wet Bulb Temperature Range 23 to 139.8 Degrees F, Humidity Accuracy +/-3 Percent (@25 Degrees C, 10 to 90 Percent) +/-5 Percent for Other RH Ranges, Accuracy +/-75 ppm +/-5 Percent of Reading, Display LCD, Auto Power Off Yes, Low Battery Indicator No, Data Hold Yes, Data Storage Yes