Happy Jack’s Flexenhance contains the active ingredients Glucosomine and Creatine. These are natural “building blocks” which help reverse the damage caused over time to joints, bones and cartilage and improve your pet’s flexibility and mobility. Glucosomine is essential in helping the body regenerate connective tissue and helps reverse damage. Creatine is the energy enhancing component that increases strength and flexibility in muscle fiber. Recommended by professional breeders & veterinarians for working dogs & older dogs, especially those with strength, endurance, & mobility limitations.