The 42 series is our 4-chamber diaphragm pump, providing up to 3.0 gallons per minute. This automatic water system pump is designed for boats and RVs with multiple fixture water systems. This automatic demand water pump has a built-in pressure switch, which automatically starts and stops when the faucet is opened and closed. This pump also is capable of supplying up to 3 fixtures. The design allows for very quiet operation, while providing reliable high-flow performance and longevity. The completely rubber mounting base absorbs vibration and reduce noise. This pump is capable of self-primimng up to 6 vertical feet, and can run dry without damage.