This professional-grade ORP and pH sense-and-dispense technology was previously only available for commercial pools. Goldline Controls now offers an economical approach, with the same level of accuracy, for residential pools. Unlike others on the market, Sense and Dispense uses a proportional feed algorithm that continuously tests the water, sampling pH and sanitizer activity, and adjusting chemical feeding on a basis proportional to the demand. Other approaches don't sample the water often enough and release larger doses, which is far less effective and can create highs and lows similar to a manual approach. 1 year limited manufacturer's warranty