Compatibility: Only compatible with eufy Breast Pump S1 / S1 Pro. Warm, Smooth Breast Pumping: Experience soothing warmth during pumping sessions with our innovative HeatFlow technology. Easy to Clean: Wash with warm, soapy water and rinse well after each use. Dishwasher, fridge, and freezer-safe for quick and easy cleaning. Soft Silicone: The durable silicone flange ensures strong suction for your breast pump while keeping the milk collector sealed. Comfy Fit: Designed for optimal comfort and an ergonomic fit, delivering a pleasant breast pumping experience. Guaranteed Reliability: eufy breast pump accessories are covered by a 90-day limited manufacturer's warranty. Lifespan: Typically lasts 3 months. Replace if suction and performance decrease with use and sterilization, or based on your usage.