Compatible with 108oz/3.2L and 67oz/2L Stainless Steel Cat Water Fountain. Additional compatible models include PLWF003. Replace the carbon filter every 4 weeks; during hot weather, replace every 2 weeks to prevent bacterial growth. Replace the foam filter every 2 months to maintain water freshness. This set includes 8 carbon filters and 8 foam sponges for easy replacement and extended protection for your pet. 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, fresh drinking water all day Before use, soak the filter in a clean bowl of water for 5 minutes to ensure proper saturation. Do not install the filter dry, as this may cause overflow. Avoid soaking the filter directly in the fountain tank to prevent dust contamination. Material: Sponge Color: White + Black Package Contents: 8 x filter elements, 8 x filter sponges Note: Only the items listed are included. Light and display settings may cause slight color variations. Measurement error allowance: +/- 1-3 cm.