At 3 GPM and 55 PSI, the 4008 Revolution takes the next step in RV pump technology. With patent-pending Flow Reaction Technology, a unique one-piece diaphragm and internal by-pass assure long life and top performance in any plumbing system. Designed and constructed for high flow, low noise, no rapid cycling and SHURflo reliability, this fresh water demand pump is super quiet, thermally protected and can run dry without damage. This pump is self-priming and mounts in any position. With SHURflo standard 1/2" NPSM ports, and a built-in check valve, the 4008 pump is a direct 2088 pump replacement upgrade.