Inkbird USB Thermometer Hygrometer THC-4-H Temperature and Humidity Data Logger, LCD Display, 16000 Data, w/ Humidity External Sensor Easily managed by PC data management software, only works for Win XP/ 7 / 8 PC It is also ideal for monitoring building services, scientific experiments, production processes, and heating, ventilation and air conditioning systems. 6-12months Battery life Double sensors: Built-in Sensor and External Humidity Sensor Especially widely used for all kinds of warehousing, logistic and cold chain