【Package Includes】You will receive 3 pieces of portable breast pump flange inserts in different sizes, 17mm, 19mm, and 21mm. It can reduce the breast shield tunnel to 17mm/19mm/21mm to adapt to changes in breasts during different physiological periods and provide better breastfeeding. 【High-Quality Material】Our breast pump insert is made of food-grade disulfide-free liquid silicone material through multiple processes. All parts that come into contact with breast milk are 100% BPA-free, so you can use it with confidence. It is very comfortable and soft to use, making it an excellent replacement for breast pump parts. 【Made for Mothers】Mothers' nipples change at different times, and our breast pump accessories come in 3 different sizes to meet your baby's milk needs anytime, anywhere. Choosing the right breast pump insert for pumping makes pumping more comfortable and efficient and avoids swollen nipples. 【Easy to Clean】These breast pump inserts are very easy to clean. Just wash and rinse with warm soapy water after each use. You can also sterilize it with boiling water at about 100 °C (212 °F), steam, or a microwave steam bag. 【Widely Compatible】Our breast pump accessories come in three different sizes and can be used with most brands of breast pumps, making them a perfect fit for all breast pumps. You can buy with confidence without worrying about the wrong size.