Comes with 4 Zones, expandable to 22 zones with optional modules. ESP-SMTe Series Smart Irrigation Control System Other Smart Sprinkler Timers claim simplicity and precision; the Rain Bird® ESP-SMTe Smart Control System delivers. Combining the proven simplicity of the Extra Simple Programming (ESP) controller family with the accuracy of weather-based control, this innovative system can now expand up to 22 zones. The ease and speed with which you can program this controller is remarkable. Simply input a few key specifics, such as your zip code, allowed watering days and the plant/soil type for each zone; the ESP-SMTe does the rest. Your irrigation system waters only when the landscape requires it. And you save 30-70% in water