2 2-nozzle packs of Monsoon replacement nozzles Create a very fine mist to keep your reptile or amphibian comfortable and healthy Replacement nozzles give you the option to grow your existing terrarium misting system Extend the system to multiple terrariums using additional Y-connectors (PT2498) and Tubing (PT2504) Up to 4 nozzles can easily be added to one Exo Terra Monsoon RS400 Misting System (for a total of 6 nozzles) The Exo Terra Monsoon Nozzles allow you to expand your existing Exo Terra Monsoon RS400 misting system (up to six nozzles) or extend the system to multiple terrariums using additional Y-connectors (PT2498) and Tubing (PT2504). We recommend using distilled water.