100% brand new and high quality Very suitable for using in freshwater and marine water. Can be cut any sizes as your needed. Lightweight softness design. Excellent water permeability. Cultivate the nitrifying bacteria for biological filtration. Dense shape makes it effective to avoid residue. Can be used again after cleaning. The Biochemical Filter has the best effect on decomposing the excrement and the forage leftover. Its multi-porous feature will avoid blockages and provide the largest adhesion area for bacteria. Material: Biochemical Cotton Sponge Large Size(L*W*H):100cm x 12cm x 2cm/39 x 4.68 x 0.78(approx) Medium Size(L*W*H):50cm x 12cm x 2cm/19.5 x 4.68 x 0.78(approx) Small Size(L*W*H):12cm x 12cm x 2cm/4.68 x 4.68 x 0.78(approx) Color:Black Quantity: 1 pc Advise: Replace the bio-sponge three month, to ensure the filtrating effect as well as the growth of the nitrifying bacteria. Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual colorof the item. Thank you