Compatible with 108oz/3.2L and 67oz/2L stainless steel cat water fountains. Additional compatible models include: PLWF003. Replace the carbon filter every 4 weeks; during hot weather, replace every 2 weeks to maintain water quality. Replace the foam filter every 2 months to keep water fresh. 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, ensuring pets drink clean, fresh water all day Before use, soak the filter in a clean bowl of water for 5 minutes to ensure proper saturation. Do not soak the filter directly in the fountain tank to prevent dust dispersion. Ensure the filter is fully soaked before turning on the fountain to avoid overflow. Material: Sponge Color: White + Black Package Contents: 8 x filter elements, 8 x filter sponges Note: This package includes only the items listed above. Other products are not included. Lighting and display settings may cause slight color variations between the image and the actual product. Measurement may vary by +/- 1-3 cm.