Keep the water in your aquarium clean and safe for your fish with this value pack of Top Fin EF-S Element Filter Cartridges. The cartridges in this 6-month supply feature activated carbons, and have proven highly effective in removing waste, odors and more from your aquarium water. Features: With activated carbon to help remove heavy metals, odors, pigments, and organic waste Refill for Top Fin BFS Bettaflo Filter and Desktop Aquariums with Element Filters 6 Count Includes: 6 Count Intended Pet(s): Fish Material(s): Carbon Color: White, Black Product Dimensions: 2.1 in L x 3.7 in W (5.3 x 9.3 cm)