Compatible with 108oz/3.2L and 67oz/2L Stainless Steel Cat Water Fountain models (e.g., PLWF003). Replace the carbon filter every 4 weeks; during hot weather, replace every 2 weeks. Replace the foam filter every 2 months to maintain fresh water. This set includes 8 carbon filters and 8 foam sponges for easy replacement and continuous protection. Three-layer filtration system: - First layer: Blocks hair and debris - Middle layer: Reduces residual heavy metals - Third layer: Promotes healthier, high-quality flowing water for clean drinking throughout the day Before use, soak each filter in clean water for 5 minutes to ensure full saturation. Do not install dry filters, as this may cause overflow. Avoid soaking filters directly in the fountain tank to prevent dust contamination. Material: Sponge Color: White + Black Package Contents: 8 x Carbon Filters, 8 x Filter Sponges Note: This package includes only the items listed. Other products are not included. Lighting and monitor differences may cause slight color variations between the image and actual product. Measurement error allowance: +/- 1-3 cm.