BACK BY POPULAR DEMAND! The most impressive play and exercise equipment for your small animal! Click the product image above to see it in action. This exercise wheel is absolutely loved by chinchillas, and other small animals. No openings or sharp edges means your pet can work out safely. Watch them run and run and run. Full bearing system means no middle-of-the-night squeaks either! The wheel is 9 inches high and 13¾ inches in diameter and handles animals from 4 ounces up to 2½ pounds. It extends 13¾ inches from the side of the cage and will fit through a cage door 9" x 12" or 10" x 10".