The days of only being able to choose from large traditional solar pool heaters are long gone. It's designed to extend your pool season by gradually increasing the water temperature by a few degrees. The unique threaded ports have been added for versatile plumbing options. Details:Black11.25" x 23" x 23"Environmentally-friendly heating energyAble to connect multiple heaters togetherPool pump or filtration flow rate should not be higher than 10,000 liters/hrPlastic and metal