"Breast shields play a key role in pumping efficiency and overall comfort. Your Medela PersonalFit Flex shield offers new Medela Flex Technology and a unique design that adjusts easily to your breast shape - its flexible oval shape can be rotated 360 degrees and adapts to your body, so you can find the most comfortable and efficient pumping position for you. Additionally, a 105-degree angle opening combined with a soft, smooth rim is made to reduce unnecessary pressure on the breast and lay smoothly for comfortable positioning, pumping efficiency, and a more natural feeling. Our PersonalFit Flex breast shields don't just remove more milk than traditional breast shields or effectively remove milk faster - these breast shields remove 11.8% more milk per minute and help moms pump more milk than when pumping with traditional breastshields. This optimizes your pumping sessions, making them more effective and more comfortable. What's Included: (2) PersonalFit Flex Breast Shields (or 1 extra set), 27 mm size These breast shells are compatible with all Medela breast pumps and are available in 4 different size options. All Medela breast shields and other Medela products that come in contact with breast milk are - and have always been - made without BPA. Use our 27mm Medela breast shield to begin personalizing your pump and enhancing your breast milk feeding experience, so you can continue to breast milk feed your little one for as long as you choose. Ensure that you're purchasing authentic Medela products - Inauthentic or counterfeit parts can vary significantly in terms of design, workmanship, and materials used, which may affect the performance of your pump and/or your pumping experience. Medela is proud to provide the quality and performance that moms have trusted for decades, making us the #1 physician recommended breast pump product in the U.S. QuintilesIMS ProVoice Survey; Nov-Oct 2017"