WARE Critter Universe Small Animal CageCritter Universe is an out of this world, totally connectable and infinitely expandable cage system. Simple to assemble and easy to clean for your convenience. The cage is constructed of durable plastic and wire. The cage features an escape proof locking door to keep your critter safe and secure. We've included a removable cage top carrier complete with a handle for easy transport of your pet. The cage includes a wheel, water bottle, bowl and tube. The Critter Universe connects with other modular systems such as Crittertrail and Habitrail as well as other Critter Universe items, such as the Expansion Kit, Tunnels and Wall Unit (all sold separately). As your critter grows you can add on and expand Critter Universe to fit his growing needs.