Self-priming, automatic-demand water pump supplies consistent water flow for up to 4 fixtures. 4-Chamber diaphragm provides high-volume water flow with reduced cycling. No accumulator tank necessary. Works with fresh or saltwater. SEAFLOs 3.0 GPM 42-Series Variable-Flow Automatic-Demand Water Pressure Pump is their 4-chamber model capable of supplying up to 3.0 GPM. The 42-Series features a Variable Flow Technology which is an internal bypass feature which allows the pump to provide the amount of water you demand without cycling. No accumulator tank necessary! The pump can be used in both fresh and salt water applications, making it ideal for supplying water to up to 4 fixtures, or being able to be used as a raw water washdown pump. The completely rubber mounting base isolates pump vibration for very quiet operation. The 42-series diaphragm pumps are self-priming up to 6 vertical feet and can run dry without harm. The built-in adjustable pressure switch automatically starts and stops the pump when the faucet is opened or closed. The pressure switch is factory set to 55 PSI pressure cutoff, but this setting can be adjusted up or down by the user. It comes with (2) 1/2 barbed fittings and (1) strainer.