Sunsun Aquarium Canister Filter Replacement Sponge for HW-303 AB / 403 AB | 2pc pack

Has a good filtering function to make water clearer. Supports to reduce the growth of bacteria’s In good quality with open pore and large surface area to promote bacteria break down. Safe for fresh and Marine water. This spare sponge will fit for Sun Sun  HW-303A, 303B and HW-403A, 403B external canister filter