Compatibility:Compatible with eufy Breast Pump E10 / E20 / S1 / S1 Pro. Customized for eufy Breast Pumps: Designed to reach every corner of your breast pump, this brush ensures thorough cleaning. Safe and Durable: The brush head is crafted from durable, food-grade PP+ material to ensure both safety and longevity. Versatile Use: Ideal for cleaning nipples, squeeze tops, and sippy cups of all shapes and sizes. Compact and strong enough to clean small parts. Gentle on soft materials. Guaranteed Reliability: eufy breast pump accessories are covered by a 90-day limited manufacturer's warranty. Lifespan: Typically lasts 6 months. Replace if suction and performance decrease with use and sterilization, or based on your usage.