From the Hunter Industries website: The Solar Sync Sensor is an advanced weather sensor that calculates evapotranspiration (ET) and adjusts Hunter controllers daily based upon onsite weather conditions. Solar Sync measures sunlight and temperature, and uses ET to determine the correct seasonal adjustment percentage value to send to the controller. The controller then uses its programmed run time and adjusts to Solar Sync’s seasonal adjustment value to modify the actual irrigation run time for that day. In addition, the Solar Sync sensor integrates Hunter’s popular Rain-Click™ and Freeze-Clik® sensors providing quick response in shutting down your irrigation system during rain and/or freezing conditions. The Solar Sync is compatible with most Hunter controllers and applicable to residences, businesses, and municipalities alike. Automatically adjusts irrigation duration based on weather conditions using on-site solar radiation and air temperature Quick ResponseTM instant rain shutoff and freeze shutoff at 3°C. Maintenance-free design with integrated battery for wireless models. Adjustable vent ring allows for shorter or longer reset period. Rugged polycarbonate housing and metal extension arm. Includes gutter bracket and wall mount with wireless models.

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