Feature: 1. COMPACT AND LIGHTWEIGHT: Mini aquarium sponge filter is compact and lightweight, saving space and making it easy to clean and replace filter pads. 2. PNEUMATIC FILTRATION PRINCIPLE: Aquarium sponge filter adopts pneumatic filtration principle to protect fish health and keep water clean. 3. SAFE MATERIAL: Fish tank sponge filter is made of environmental friendly and non toxic material to protect water quality and fish safety. 4. HIGH ADSORPTION CAPACITY: Aquarium biochemical water filter has strong adsorption capacity and can remove most of the impurities in the water. 5. SCOPE OF APPLICATION: Fish tank biochemical water filter has even water discharge. Suitable for many sizes of fish tank and grass tank. Specification: Item Type: Aquarium Sponge Filter Material: Plastic, Sponge, Rubber. Package List: 2 x Filter Cotton2 x Filter Cotton Support Rod2 x Filter Material Box1 x Main Water Pipe1 Bag x Filter Material