This expandable travel habitat is perfect for all hamsters, gerbils and mice. The convenient carrying handle makes the journey and transportation easy. Attach to other CritterTrail habitats to create more room for your pet to explore or use to keep pets safe during cage cleaning. This cage connects to other CritterTrail expandable habitats to create an add-on room when not in use as a carrier. Connecting to other CritterTrail Habitats requires a CritterTrail Fun-nel Tube Accessory; sold separately.