6 Duckbill and 4 Diaphragm Silicone Breast Pump Parts-Compatible with S9/S12 MomCozy. The diaphragm is used to help the breast pump maintain the seal to prevent milk leakage. 【Closed System Design】:Silicone duckbill valve designed to prevent back-flow of breast milk, help to drain breast milk to the bottom of container, no loss of suction.
