The Deluxe CritterTrail Water Bottle has been specifically designed for CritterTrail homes. The new Deluxe Water Bottle fits all CritterTrail® homes and its premium design includes Super Pet's unique drip-resistant spring-loaded sipper. You can also add a second CritterTrail® Water Bottle to your pet's home if you need to close an opened accessory hole on the CritterTrail rooftop. For hamsters, mice, gerbils or other small animals.