The Hydra LG Humidifier will automatically regulate the humidity inside large humidors of up to 8 cu ft and the LG up to 16 cu ft. You may further extend the capacity of the large Hydra by adding up to 3 optional external fans. The Hydra Fan Kit contains a splitter, a connector and a ribbon cable in addition to the fan itself. Each port splitter allows for up to three external fans to be attached to the Hydra.