The Medela Pump In Style® with MaxFlow is an easy-to-use breast pump designed for maximum efficiency. With its MaxFlow micro-vibrations and 2-Phase Expression Technology, this intuitive breast pump takes the guesswork out to deliver more effective pumping. Plus, this closed system breast pump comes with a convenient battery pack (batteries not included). So you can pump away from a power outlet. For more information on the Pump In Style with MaxFlow, visit the Medela website.