Excellent materialThis ball is made of high quality plastic, durable, wear -resistant and can be used for a long time Transparent designThe ball has a transparent design with which your pet can watch his condition when playing Easy installationThe toy ball is simple and convenient to install, simply align the two hemispheres and tighten the cover and it is not easy to fall down Small and lightThis toy running ball is small and light, with a diameter of 12 cm, suitable for small hamsters such as dwarf and racing mice VENT DesignThere are several safety ventilation holes on the running ball to ensure that your pet can play safely Features: Robust and durable, not easy to damage Easy to install and not easy to fall down Safe ventilation hole design The diameter is 12 cm, suitable for dwarf and racing mice, etc., not suitable for Syrian hamsters / hedgehogs / chinchillas and other large hamsters Specification: Material: Quantity Color: Transparent Diameter: 12 cm The package includes: 2 ball Features: Robust and durable, not easy to damage Easy to install and not easy to fall down Safe ventilation hole design The diameter is 12 cm, suitable for dwarf and racing mice, etc., not suitable for Syrian hamsters / hedgehogs / chinchillas and other large hamsters Specification: Material: Quantity Color: Transparent Diameter: 12 cm The package includes: 2 ball