Medela replacement parts are great for always having clean, extra breast pump parts ready to go at a moment's notice. Our authentic spare valves and membranes are engineered, tested, and approved for use specifically with your Medela breast pump – Spare parts that are not authentic can vary significantly in terms of design, materials used, and overall workmanship, all of which may affect the performance of your breast pump. These Medela extra parts, consisting of spare membranes and valves, are conveniently compatible with all Medela breast pumps EXCEPT for our Freestyle pump. This means that you can use these sets with breast pumps like the Pump in Style, Swing, Sonata, and Symphony and can rest assured knowing that you have Medela replacement parts on hand for whenever and wherever you may need them. These extra valves and membranes are also compatible with all Medela PersonalFit breast shields. What's Included: (2) Valves; (2) Membranes As always, all Medela breast pump parts and accessories that come into contact with breast milk are made without BPA for the peace of mind that every mom deserves when it comes to their baby. Find out why Medela is the first choice of doctors and moms today!