High Quality MaterialThe aquarium filter bags are made of high quality nylon and plastic zipper, durable and corrosion resistant, breathable and not easy to break, serve you for a long time. Filter Bags SizeEach mesh bag measures approx. 15 x 20 cm / 6 x 7.9 inches, the diameter of the mesh holes is 2 mm / 0.08 inches, smaller hole size can improve filtration. Zipper Design Each filter bag with zipper, the zipper is made of plastic, so it will not rust or harm the health of the fish, it is very ventilated for the fish to stay inside by its mesh grids, which are easy to fill and empty, it is not easy for the fish to escape. Function The aquarium filter bag can help you filter impurities in the aquarium, make the water cleaner and more hygienic, and prevents the growth of bacteria, providing a better environment for the aquatic organism. Wide Application Ideal for bio-balls, activated carbon, ceramic remover and ammonia, fine filtering, charcoal media and smaller particle media, it is available for aquarium, pool, pond and any other occasions. Features: Durable Material: The filter bags are made of corrosion-resistant nylon, which are strong and durable and will not be deformed or broken. The zippers are made of high-quality plastic and will not rust or cause any harm to fish. Easy to Clean: The aquarium mesh bags are easy to fill and empty with a zipper design to keep the filter media secure; The bags are very easy to fill and clean, can be used multiple times. Small Mesh Hole: Holes Diameter: 2 mm / 0.08 inch. Media smaller than 2 mm will leak out of the bag. Therefore, it is not suitable for use with smaller particle media, such as Purigen, Phosguard, Gel Mix, Activated Carbon, etc. Specifications: Material: Nylon Color: White and Black Size: 15cm * 20cm / 5.9 * 7.8in Hole Diameter: Approx. 2mm Package Including: 10 * White Filter Bags 10 * Black Filter Bags