Features8 Count Replacement Duckbill Valves and 2 Count Silicone Membranes for Spectra S2, Spectra S1, Spectra 9 Plus breastpumps.THIS IS AFTERMARKET PART MADE BY PumpMom. Not Original Spectra S2 Pump Parts.SAFE MATERIAL - Made with Food Grade Silicone, and can be sterilized in water steam or boiling water.Clean with soapy water and rinse with clean water. Do not use hard brushes. Clean the thin tips with fingers. Do not use dishwasher.100% MONEY BACK GUARANTEE - If you experience any issues we offer a complete No Questions Asked Money Back Guarantee.