Rain Bird® ET Manager is a simple, powerful irrigation management solution works with virtually any controller, converting a conventional irrigation system into a weather-smart one. The ET Manager helps to maintain the optimum moisture balance in your soil. As the weather changes, your ET Manager receives updates automatically every hour and only allows your controller to water when needed. ET Manager technology is based on the Irrigation Association-endorsed, ASCE-standardized evapotranspiration (ET) equation, and includes data from all required climatic variables: solar radiation, temperature, wind, and humidity. An onsite rain gauge can be added for rainfall. The result – significant water savings, deeper root systems, and a healthier landscape.