100009481 Size: Medium / 1 Pack Features: -Cartridge. -Patented dual-sided replaceable dense-floss cartridges contain over 25% More activated carbon than leading brands. -Designed to ensure even distribution of carbon throughout for more filtration and longer cartridge life. -Features simple, no mess replacement. Color: -Whites & Tans. Pet Category: -Fish. Product Type: -Filter Cartridges.