Compatible with eufy Robot Vacuum 3-in-1 E20. To keep your E20 Robot Vacuum operating at peak efficiency, replace the brush every 3¨C6 months, depending on usage frequency. Soft, flexible bristles clean effectively without damaging floors or furniture. No tools required, easy to replace the side brush. Important Note: For the best performance and to extend your robot vacuum's lifespan, we strongly recommend using authentic eufy replacement parts. We¡¯ve received customer complaints about issues with non-compliant sellers providing substandard alternatives.