For fish farming: This Physical Filtration Filter & Cotton Parts is designed specifically for the Smart Aquarium. It features multi-layer filtration, no clogging, excellent water permeability, and fast filtration. Optimal Filtration Efficiency: Provides excellent physical filtration performance, effectively capturing fine particles and ensuring a clean aquarium. Expiration Date: This refers to the overall performance of the aquarium, not the performance of individual filter elements. Material: Made of high-quality material, the filter cotton is while maintaining high filtration efficiency, reducing the need for frequent replacement. Easy Installation: This replacement filter cotton is easy to install and simple to maintain, ensuring your aquarium always maintains optimal efficiency. Color: As Shown Material: plastic Package Contents: 1 * Physical filtration module 10 * 8D Filter Cotto 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.