Cute house for small pet: Makes a large temporary holding area to keep your furry friend while you clean their home 4.7-inch diameter for dwarf hamsters, mice. Meet the sports needs of small pets: Fun exercise toy to maintain your pet’s alertness and agility. Provides interactive fun for the pet and the pet owner. Specification: Material: quality plastic Size: diameter 4.8 inch/ 12 cm Color: green, blue Package included: 2 x Hamster exercise running balls Warm notes: Due to the difference of light and screens, the product you receive may not be exactly the same as the picture. If you have any questions about the product, you can contact us by e-mail, we will solve it for you as soon as possible.