Conditon: 100% Brand New_x000D_ Item Type: Biochemical Filter Sponge_x000D_ Material: Cotton_x000D_ Color: Black_x000D_ Outer Diameter: Approx. 4.9cm/1.9in_x000D_ Hole Diameter: Approx. 2cm/0.8in_x000D_ Length: Approx. 9cm/3.5in_x000D_ Usage: Fit for aquarium filter 1The sponge can effectively prevent the inhalation of shrimp and small fish, and prolong the use of filter materials. 2Prevent weed from entering the filter tank to reduce the filtering frequency. 3Can clean the water inlet pipe, reduce sewage deposition, and reduce the attenuation of the filter element flow. 4The material has great thickness, it is durable and very suitable for using in freshwater and marine water. 5Lightweight, softness design and excellent water permeability,dense shape makes it effective to avoid residue.10 xBiochemical Filter Sponge