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; in 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. Three-layer filtration system: First layer traps hair and debris; middle layer reduces residual heavy metals; third layer promotes healthier, high-quality flowing water, ensuring pets have access to clean, fresh water daily. Before use, soak the filter in clean water for 5 minutes to ensure proper saturation. Do not install the filter dry or soak it directly in the fountain tank to avoid clogging. Fully saturate the filter prior to operation to prevent overflow. Material: Sponge Color: White + Black Package Contents: 8 x Carbon Filters, 8 x Foam Sponges Note: This package includes only the items listed. Other products are not included. Lighting and monitor settings may cause slight color variations between the image and the actual product. Measurement may vary by +/- 1-3 cm.