HSH-Flo 3/4'' Circulator Pump 115V Hot Water Circulation Pump For Solar Heater System Voltage/Freq:115V/60Hz Max head:20/16/13FT No leakage, low noise, environmental protection, aesthetics, ease of installation and so on. High temperature resistance, antifraying,long life, full-automatic, maintenance-free, super silent, Built-in high sensitive electronic sensors, the water will be flow when we open the switch.