Roll, spin, solve and play, the GURU Duo-Ball keeps dogs challenged and engaged through intentional multi-functional play by addressing instinctive behaviours. Treats slowly make their way from the inner ball to the outer ball before finally reaching - and rewarding - the dog, all while tumbling about the floor for engaging, fun-filled play sessions. Made with Chew Pro; GURU's ultra-durable, custom, non-toxic thermoplastic rubber formulated specifically for tough chew sessions.