Medela Breast Shields, Connectors, Valves and Membranes (21mm Shields) Go to amazon.com Related posts Best medela membranes set for 2022 FeatureSet includes all items needed to replace yoursYou get2 Personal Fit Breast Shields2 Valves and Membranes2 Connectors. DescriptionJust add your pump and tubing and you are all set to go. This is not in retail packaging and only comes in bulk.