Description: 100% brand new and high quality Provides biological filtration to the aquarium, helps to stable water quality Increase the oxygen solubility Working noiselessly,good permeability, easy to clean It reduces noise from air pump and consumes lowest wattage Specifications: Color: Black Material: Biochemical cotton Style:XY-2830, XY-2831, XY-2822 Size: XY-2830: 14.5*9CM XY-2831: 14*14CM XY-2822: 17*23CM Conversion: 1cm= 0.39'' Notice: 1.Please use aquarium water to wash the sponge, don't use hot water. 2.Please soak it with aquarium water for 5 minutes before use, It will be easy to digest bacteria colonies. Package Included: 1 * Biochemical Filter (Style base on your selection) .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }