Features: Ultra-thin design, save space inside the aquarium tank, more beautiful. Comes with filter sponge, bio balls, air stone inside, more surface area for beneficial bacterial to colonize and faster cycling, keep your fish tank clear and clean. Easy to set up: simply install an airline into the unit and turn on the air pump, great way to clean and oxygenate your tanks; Easy to clean: simply squeeze the sponges in tank water. Easy to use: simply place it anywhere at the bottom of aquarium Suitable for shrimp tank, betta tank, breeder tank, goldfish, discus, guppies, fry, baby fish or other fish. Specification: Material: Plastic S: (Dia*H) 8*5.5cm / 3.15*2.17 inch L: (Dia*H) 10.5*5.5cm / 4.13*2.17 inch Package List: 1 x Aquarium Filter Note: Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering. .