Enables Medela Breast Pumps (Pump in Style, Lactina, Symphony, Swing) to work with Avent wide-mouth bottles, Spectra bottles (Note: This ring DOES NOT work with Avent VIA storage cups).

Includes 4 conversion rings plus 4 sealing rings to avoid many leaking events. You can pump directly into Avent bottles. BPA free, dishwasher safe, retail pack, sealed by manufacturer.

Also Adapts to: Evenflo Comfort Select, Ameda Purely Yours, Lansinoh Double Electric, Playtex Embrace, Dr. Brown's Natural Flow Electric/Manual