Characteristics: 1. Made of high-quality plastic that is sturdy and durable. 2. Equipped with suction cups to ensure stable installation of the product. 3. It will do better when you combine biochemical, sponge and physical filtration. 4 . Removable, washable, replaceable cotton filter. 5. Two sizes to choose from, it's easier to decide which one suits you best. Specification: Material: plastic; Color: as shown in the pictures Type: LH300 Size: LH300: 189 * 67mm / 7.4 * 2.6in (H * bottom diameter) Package List: 1 * Filter 4 * Suction Cup How to install: Use the air hose to connect the product to the air pump. Connect the air pump, if water or bubbles come out of the water outlet, it means it is working normally. If the air pump is lower than the water, install a check valve. Note: The fluidized bed initially rises and needs to be soaked in water for 1-2 days to get slurry and tumble. It should be connected to an air pump. Please be aware of: