Wearable Breast Pump Parts: 24mm Flange, Duckbill Valve, Diaphragm For S18 S21. Discover Ultimate Comfort and Convenience with Our Breast Pump Parts Milk Collector Cup Set. Designed for Modern Moms, These Wearable Breast Pump Accessories Offer a Universal Fit for Nipple Sizes 21-23mm, Easing Soreness and Swelling While Ensuring Your Baby Receives Fresh Breast Milk, and You Enjoy More Restful Nights. Crafted with Safety in Mind, These Accessories Are BPA-free and Made from High-quality Silicone. They Meet Stringent Safety Standards, Including US FDA Approval, Ensuring Your Baby's Milk is Safe. Compatible with Popular Pump Brands, These Collector Cups Can Hold Up to 160ML/6oz, Perfect for Early Morning Pumping Sessions. The Easy Assembly Allows Even New Moms to Quickly Put the Parts Together, and the Soft Silicone Shield Fits Discreetly Under Your Bra for Maximum Comfort. Prevent Leaks with the No-backflow Design. The Silicone Diaphragm and Duckbill Valve Ensure Breast Milk Flows One Way, Providing Efficient Suction Without Spills. Cleaning is a Breeze—sanitize Using Water Steam, Boiling Water, or Microwave-steam Bags. Lightweight at Just 150g, These Cups Offer Hands-free Pumping, Perfect for Busy Moms at Home or on the Go. Summary of Features: - Universal Fit: Suitable for Nipple Sizes 21-23mm - Safety First: BPA-free, Meets US FDA Standards - Compatibility: Works with Popular Breast Pump Brands - Capacity: Holds Up to 160ML/6oz - Comfort Design: Soft Silicone Shield, Discreet Under-bra Fit - Leak-Proof: No-backflow Design with Duckbill Valve - Easy Cleaning: Sanitize Using Steam or Boiling Water - Portable: Lightweight and Ideal for Multitasking Pump with Ease and Freedom, Enhancing Your Breastfeeding Experience..