CONTENTS: 2ct 23mm flanges and 2ct duckbill valves compatible with Spectra S2, Spectra S1 and Spectra 9 Plus breastpump. Made by Maymom. Not Original Spectra Flanges, Spectra Duckbill Valve. Can use Maymom flange for Spectra pump or Maymom duckbill valve for Spectra pump parts. Made by Maymom, not by original spectra company. Maymom is not affiliated with Uzinmedicare, the trademark owner of spectra. COMPATIBLE AND INTERCHANGEABLE with Spectra pump parts. Maymom pump parts perform the same suction power as OEM parts, Spectra S2 pump parts, Spectra S1Plus accessories. MAYMOM DUCKBILL VALVES features "easier to plug in and remove", "durable quality" and "color options" MAYMOM FLANGE can work with Spectra wide-neck bottle (wide-mouth bottle), Compatible with Avent bottle, and Maymom widemouth bottle. Available Flange sizes:13mm, 15mm, 17mm, 19mm, 21mm, 24mm, 25mm, 27mm, 28mm, 29mm, 30mm, 32mm. BPA/DEHP FREE. FDA compliant for food contacts. Tested by independent labs for safety. Test report online available for reference. Products in retail pack sealed by manufacturer; NO problem with dishwasher top rack, water steam cleaning, boiling water or microwave-steam bags. Contents: 2 Flanges and 2 duckbills Made by Maymom, not by original spectra company. Maymom is not affiliated with Uzinmedicare, the trademark owner of spectra.