Warm Tips: Our Flange Inserts only suitable for 24mm Shields/Flanges, not fit for 27mm Shields/Flanges or other size. The flange insert size is important for comfort and efficient pumping.Some moms have the experience of nipple swelling while milking, so it is important to observe the appearance of the nipple during pumping. The flange insert is recommended to be replaced every 1 to 2 months.Please choose the right size. Frussonia flange inserts provide a smaller adjustment option, suitable for the original 24mm flange breast pump, reduce 24mm size to smaller size, make the breast pumping more comfortable and efficient for the smaller nipple mom. It is a good helper for those moms who are anxious by the little milk output, which can get more milk output from pumping without pain. They help maximize milk expression while minimizing nipple trauma or irritation.