Compatibility: This set of 8PCS flange inserts comes in sizes 21mm, specifically designed to be compatible with the 24mm flange/shield of most breast pumps. Whether you're using Momcozy, Medela, Spectra, or other popular brands, these inserts accommodate the changes in nipple size that mothers experience throughout various stages of lactation. Easy to clean: Keeping your pumping accessories clean is essential for maintaining hygiene. These inserts can be effortlessly cleaned in dishwashers, but we recommend placing them on the top rack for optimal results. After each use, it's advised to clean the pump accessories with water at a temperature of 100°C/212°F to ensure thorough sanitation. As an added convenience, the set includes a complimentary sponge brush to facilitate meticulous cleaning of the flange inserts. Safe and Soft: Your comfort and safety are paramount. That's why our ZÜCÜBéBé flange inserts are crafted from BPA-free food-grade materials, guaranteeing both safety and reliability. The soft, pliable material offers a gentle and comfortable experience for mothers. It seamlessly adapts to nipples of various shapes and sizes, not only enhancing pumping efficiency but also minimizing any potential friction or pressure on the nipples. More Choices: We understand that finding the perfect fit is crucial for a successful pumping experience. In addition to the sponge brush, each set of ZÜCÜBéBé flange inserts includes a silicone measuring card for nipples, allowing you to select the ideal size with confidence. Before each pumping session, take a moment to measure your nipple size to ensure a precise fit with the flange inserts. Rest assured, we're committed to providing exceptional customer service and support. If you find that the size doesn't quite meet your needs, please take advantage of our hassle-free replacement service. Tips: Nipple size can fluctuate throughout different stages of breastfeeding. For optimal comfort and effectiveness, we recommend replacing the flange inserts every 1-2 months. If you're confident about your nipple size, feel free to choose the specific size of flange inserts that suits you best. However, if you're uncertain about your size, we suggest opting for our 10PCS flange inserts set. This way, you'll have the flexibility to experiment and find the perfect fit for your individual needs. Flange Insert 21 mm (8PCS) for 24mm Flange/Shield of Most Pumps, BPA Free Inserts, Compatible with Medela/Spectra/TSRETE/Elvie/Momcozy/Bellababy Breast Pump 24mm Shields/Flanges