Filters and Replacement Media - 4 Carbon and 4 Polyester PadsThe Bio-Matrix cartridge provides triple filtration for aquarium water, The dense white polyester filter media gives effective mechanical filtration while the activated carbon-impregnated polyester filter adds chemical filtration, Genuine Supreme replacement media are available in four money-saving, convenient packs, This is replacement media only which does not include the plastic cartridge framework, SKU: RPS26980