Spare Parts - Ultrafine Filter Cartridges 9991432-R4 for Maytronics Dolphin Pool Robots, Compatible with Delphin Nautilus CC Plus, M400 and M500. Product Features: 1. Ultrafine Filtration: The pleated filter media is used to filter all types of ultrafine debris in the pool, such as: B. fine sand, algae, leaves, etc. 2. Sturdy and Durable: ABS plastic frame, more durable. If used correctly, these ultra-thin filters can last 2 to 3 years. Compatible Models: ✔ For Delphin Nautilus cc plus filters. ✔ For Maytronics Dolphin Parts 9991432. ✔ For Dolphin M400 M500 filter. ✔ For Delphin M4 M5 pool cleaners. ✔ For Delphin Orion, Deluxe 3, Atlantis filter, Apollo, Apollo Plus, DX3, DX3s, DX4, DX4s, Sigma, Odyssey, Oasis Z5i. Product Features: Dimensions: 10.43" x 6.3" < p>Contents: Set of 4 Dolphin Pool Robot Filters. Tips: 1. Rinse the filter every 4-6 weeks for optimal performance. 2. When changing the filter, always follow the filter's instructions for use.