lasuroa 4pcs Filter Cartridges for Topfin Top Fin EF-S & BF5 BETTAFLO, 3.7x2.1 Inch Fish Tank Filter Carbon Cartridge Replacement Accessories for Aquarium Water Filtration

["Package Content: You will receive 4 pieces of fish tank filter cartridge replacements. Sufficient quantity will meet your daily use and replacement needs.","Compatibility: These filter cartridges are compatible with Top Fin EF-S, BF5 BETTAFLO filter and desktop aquariums. Please note that our product is not sponsored or endorsed by, or affiliated with the brands it fits, including Top Fin.","Product Material: Our filter cartridge replacements are made of premium APS and activated carbon, which can effectively remove impurities, promoting a healthier aquatic environment and clear water.","Easy Installation: Simply rinse the new cartridge to clean loose carbon particles, then insert into the filter chamber. Make sure the cartridge fits completely into the filter chamber.","Optimal Replacement Schedule: It is recommended to replace the filter cartridge every 2-4 weeks to keep your aquarium water consistently clean and safe for fish and other aquatic life."]