Purina ONE True Instinct Lean Muscle Support Real Beef Dry Dog Food is a high-protein formula featuring real beef as the #1 ingredient to help maintain lean, strong muscles. It delivers 32% protein (the highest level in Purina ONE) and includes twice the tender meaty morsels for taste and texture. This natural recipe has no poultry by-product meal or artificial additives, helping your adult dog stay fit and energized. Available in Multiple Sizes