Many small pets require a good physical workout. Lee s offers the most complete line of small-animal exercise balls to satisfy the needs of most small animals from dward hamsters to ferrets and chinchillas. Kritter Krawlers and Komet Krawlers allow pets the freedom to roam while being safely confined and they quickly learn to maneuver aroound common household obstacles with ease. Available in colored clear or glow-in-the-dark. The ribs inside to provide better gripping power for pets (Except for Dwarf size). Shatter-resistant plastic well ventilated. Designed for use by hamsters gerbils and other small animals. Designed for use by hamsters gerbils and other small animals. Ideal for guinea pigs small exotic rats hedgehogs and chinchillas. Ideal for guinea pigs small exotic rats hedgehogs and chinchillas. The Giant size has a whopping 12-1/2 dia. perfect for guinea pigs ferrets large exotic rats hedgehogs and other small animals. The giant size has a whopping 12-1/2 dia. perfect for guinea pigs ferrets large exotic rats hedgehogs and other small animals.