This pump has an economical brush-type motor that may be used with a 12- or 24-volt battery system, or directly from an 20-watt 12-volt PV module. It has a 7,000-hour life expectancy. It works well as a circulating pump between a tank and solar collector in a domestic hot water system. It also functions well as a circulating pump in a radiant floor heating system that requires less than 5 gpm of circulation. Brushes last for 3-5 years and are easily replaced without removing pump from plumbing.