Pack of 6 High-Efficiency Spring Filter Cartridges meticulously designed to capture large debris without quick clogging. Each cartridge measures 10 1/2inch x 6 3/8inch, expertly calibrated for use right after pool openings or for pools encountering heavier than usual debris. Compatible with Dolphin Robotic Pool Cleaners: for Nautilus CC Plus, Oasis Z5i, Aquarius XL, Odyssey, C3, C4, Sigma, M200, M400, M500, M4, M5, Bio, Triton Plus (old), Liberty, wave 65, and Wave 90. Part number: 9991433-R4 The Spring Filter Cartridges are designed to only trap larger debris and let fine debris pass through to prevent the cartridges from being clogged as quickly when the pool is especially dirty, like when you open the pool in spring. plastic frame more sturdy and durable. The premium spring filters can last 2-3 years. Please rinse the filter every 4-6 weeks for optimal performance. Protect the Pool Cleaner: The cartridge filter can effectively prevent dust and other particles from entering the cylinder, reduce the wear and tear of the cylinder, ensure sufficient and clean air into the cylinder, prolong the service life of the engine and provide stronger power<br><br>Replacement Number: 9991433-R4 Colour:Black+White Material:plastic<br><br>Package Contents: 6 x Pool Cleaner Filter<br><br>Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.