The Kaytee Comfort Small Animal Exercise Wheel provides a fun fitness experience for small animals without making loud creaking noises. This wheel features a safe running surface with ridges and a “tail-safe” design. The included heavy duty wire stand lets you use it as a free-standing wheel, or you can attach it to a wire cage with the two-way clip. Choose the 8.5-inch wheel for hamsters, gerbils and hedgehogs. The 12-inch wheel is ideal for chinchillas and rats.