GENERAL HT50 Temperature/RH/GPP/Wet Bulb Data Logger. More details: Temperature/RH/GPP/Wet Bulb Data Logger, Compact, USB Compatible, Temp. Range (F) -4 Degrees to 158 Degrees , Relative Humidity Range 0 Percent to 100 Percent, Dew Point Range 70 Degrees to 115 Degrees F, Accuracy +/-0.7 Degrees F (0.4 Degrees C) Temperature, +/-3 Percent RH, Battery Life 1 yr., Sample Point Storage 16, 300 Pairs of RH and Temperature Readings or 10, 000 RH and Temperature Sets Plus IRT Readings, Remote Probe No, Digital Readout Yes, AC Adapter No, Waterproof No