The 41-Series pump provides high volume water flow with reduced pump cycling, thanks to the quad chamber diaphragm and internal bypass. These models are designed to run on water systems with no accumulator tank necessary, and up to five outlets. It is also suited for use with a holding tank water system, as may be found in a boat, RV or remote cabin. It provides up to 2.7 gallons per minute. The 41-Series pumps are self-priming, can run dry without damage, great performance, reliable and low current. This automatic demand water system pump has a built-in pressure switch, which automatically starts and stops the pump when faucet is opened and closed.? They're easy to install, service and winterize with quick snap-in port fittings.