Milky Mama - Choosing the correct flange size is super important when it comes to pumping comfort. Too big or too small and you may struggle because it won't be as comfortable
Breast Shield Sizing Guide: How to Get the Right Fit – Cimilre Breast Pumps
Breast Pump Flange Sizes: A Comprehensive Guide
Flange Size Chart
What Happens if Your Pump Flanges are Too Small? — Genuine Lactation