The Medela swing breast pump incorporates an efficient 2-phase expression technology that increases breast drainage for higher milk output. The Medela single breast pump comes with a 24-mm. personal-fit breast shield for comfortable pumping. The single breast feeding pump also has a 1-touch let-down button for quicker milk flow. You can adjust the speed and vacuum settings according to your comfort level. It comes with a belt clip and neck and shoulder strap for convenient pumping. Pack all the contents neatly in the provided drawstring bag to keep everything in one place. Any component that comes in contact with breast milk is BPA-free for safety. This battery-operated breast pump comes with milk bottles, connector valves, an AC adaptor and battery valves.