Breast Pump Flange & Valve Set Compatible With Spectra S1 S2 9 Plus Replacement. Enhance Your Breastfeeding Experience with Versatile and Reliable Breast Pump Accessories Designed to Fit Seamlessly with Spectra S1, S2, and 9 Plus Models. This Set Includes Two 21mm Flanges and Two Duckbill Valves, Ensuring Consistent Suction Power Equivalent to Original Equipment Parts. These Pieces Are Perfect for Mothers with Nipple Diameters Between 16-18mm (measured Before Pumping). Crafted from BPA-free Materials, These Accessories Can Be Easily Sanitized Using Water Steam, Boiling Water, or Microwave-steam Bags for Your Convenience and Peace of Mind. Key Features: - Compatibility: Works with Spectra S1, S2, 9 Plus, and Compatible with Wide-mouth Bottles Like Spectra and AVENT. - Set Includes: 2 Flanges (21mm) and 2 Duckbill Valves. - Versatile Flange Sizes: Options Available from 13mm to 30mm. - Easy Installation: Duckbill Valves Are Simple to Install and Remove. - Safety: Made from BPA-free Materials Suitable for Sanitization..