The 2-in-1 breast pump can be used as a single or double electric breast pump, and has two separate phases to simulate baby's natural sucking pattern. Phase 1 provides rapid suction to stimulate the breasts and initiate milk flow. This is then followed by Phase 2 - slower, deeper suction to maximize milk flow. Once in Phase 2, the Expression Phase, the pump gives a choice of the three most effective pumping rhythms designed to simulate natural feeding patterns. Once in the chosen style, mum can adjust the suction level to maximize milk production and comfort. The pump is effortless to assemble, use and clean, and is as effective as a hospital grade pump.