SHT2x Digital Humidity & Temperature Sensors Sensirion SHT2x Digital Humidity and Temperature Sensors contain a cost-effective version with the SHT20, a standard version with the SHT21, and a high-end version with the SHT25. The complete over-molding, except for the humidity sensor area of the Sensirion SHT2x, protects the capacitive humidity sensor against external impact and facilitates excellent long-term stability.