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 fresh water. 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 clean water for 5 minutes to ensure proper saturation. Do not install the filter dry, as this may cause improper water flow or overflow. Avoid soaking the filter directly in the fountain tank to prevent dust dispersion. Material: Sponge Color: White + Black Package Contents: 8 x Carbon Filters, 8 x Filter Sponges Note: The package includes only the items listed. Other products are not included. Product color may vary slightly due to lighting and monitor settings. Measurement may vary by +/- 1-3 cm.