Breastfeeding mamas, these replacement parts are an absolute essential for keeping your wearable pump working perfectly! The set includes 4 duckbill valves and 2 silicone diaphragms - exactly what you need to maintain strong suction and prevent backflow. They're designed to fit popular brands like Momcozy, TSRETE, Medela, Spectra S12/S9 and many others (check compatibility list!). The food-grade silicone is BPA-free and FDA-compliant, so you can feel completely safe about your baby's milk. What's really important is replacing these every 3-6 months - worn parts can significantly reduce pump efficiency, and these keep your pump performing like new. The included storage case is so handy for keeping everything organized and clean when you're on the go. Cleaning is simple - just use boiling water, steam, or microwave sterilizer bags. As a pumping mom myself, having fresh replacement parts on hand makes such a difference in both comfort and output. Whether you're stocking up for yourself or buying for another mom, these affordable replacements are way cheaper than buying from the pump manufacturer. They arrive neatly packaged and ready to use - one of those simple purchases that makes the pumping journey so much smoother!