FULLY COMPATIBLE:This flower fountain filter is completely compatible with DEWEL pet flower water fountain. Size: 4.92 x4.92 inch. DOUBLE FILTERS: Top quality cotton and premium active carbon remove chlorine, impurities and odors, catch hair and debris, make water in the fountain fresher, better tasting. 4 PACKS IN ONE SET: You will get 4 pieces of pet fountain filters by buying this product, which is worthy with such high quality. EASY TO USE: Rinse the filter with water thoroughly before use, replace it every 2 to 4 weeks to maintain water freshness. FREQUENCY OF REPLACEMENT: We suggest to replace it 2-4 weeks to keep the water fresh and clean.