21mm Flange Replacement Kit

This full replacement kit includes a 21mm flange, duckbill valve, backflow protector, tubing, and bottle — all made from medical-grade silicone. Dimensions and compatibility are precisely engineered for Spectra S1, S2, 9 Plus, and Synergy Gold breast pumps. The flange measures 21mm in diameter (±1–3cm tolerance), and the entire set is lightweight and designed for repeated sterilisation and daily use. The duckbill valve delivers consistent, responsive suction performance over time, while the integrated backflow protector prevents milk or moisture from entering the pump motor — extending device lifespan and maintaining hygiene. The 21mm flange offers a snug, comfortable fit for users with smaller nipple anatomy, supporting more effective milk expression and reduced tissue discomfort during longer sessions. All components disassemble easily for thorough cleaning — the silicone parts are dishwasher-safe (top rack) and compatible with steam or boiling sterilisation. Tubing is flexible yet kink-resistant, ensuring secure, leak-free connections to both flange and pump body without frequent reseating.