PR750 series high-precision temperature and humidity recorder (hereinafter referred to as "recorder") is suitable for temperature and humidity testing and calibration of large-space environment in the range of -30℃~60℃. It integrates temperature and humidity measurement, display, storage and wireless communication. The appearance is small and portable, its use is very flexible. It can be combined with PC, PR2002 Wireless Repeaters and PR190A data server to form the various testing systems that are suitable for temperature and humidity measurement in different environment.