Six pack of three different medias. 2 x boxes carbon this is a high quality palletised absorptive media that usually placed into the top of the filter. 2x boxes biological media which is placed below the carbon and 2 x boxe Glass rings which is mechanical and biological and is inserted at the bottom of the filter. This 6 pack is suitable for all canister filters. All media is packed into sewn bags which are easily placed in the media trays for ease of handling and subsequent washing. When washing use water from the fish tank as this will protect the the aerobic and anaerobic bacteria (good bacteria) and won't upset the chemical /biological balance of your aquarium. Suitable for Sunsun, Super Ehiem, Jaebo, Rena, in fact almost any canister filter. Free frieght.