High Efficiency Pool Filter：High efficiency robotic cleaning filter that removes pool dirt and debris, such as leaves, dust and diatoms. It makes your swimming pool spotless. Premium Quality：ABS plastic frame, more durable. At the same time, it can firmly support the filter layer and prevent it from breaking during operation. Recommendation：Washable and reusable, these filters can last 2-3 years if used properly. Rinse the filter every 4-6 weeks for best performance. Compatible With： for Dolphin M400, M500. The same model 9991432-R4.