The Spectra Essential Extras Kit is perfect for the working mother pumping with the Synergy Gold, Spectra 9 Plus, Spectra M1, Spectra S2, and Spectra S1 as well as the S3PRO. When there is no time or place to wash breast pump parts, this kit gives you two extra sets of flanges with valves and air dry bag to quickly and safely stow away and wash later! To assure quality, these replacement parts are genuine Spectra brand replacement parts. Includes four breast shields with valves in your choice of 24mm or 28mm size plus a high quality air dry bag with hand loop and premium stitching made to last throughout your pumping journey! Note: Zipper color on dry bag may vary.