This is the PCS3 Solar Pool Heater Heat Exchanger sold by itself. You supply all the required valves and electronic controls to either operate it manually or to automate it. Please note that the PCS3 solar pool heater heat exchanger can heat and also cool your swimming pool. And, if you operate it manually, you might get mixed results. That is why we recommend the Auto System Package, which is our most popular solar pool heating system sold.