Calcium Needed for strong bones, proper muscle function. min. 18% Iron Carries oxygen in the blood. Manganese Required for metabolism of fats and sugars. Potassium Needed for normal heart amd muscle activity. Zinc Promotes a healthy immune system. Copper Helps keep blood vessels flexible for good circulation and promotes healing Magnesium Activates enzymes for absorption and transportation of nutrients. Phosphorus Releases energy from carbohydrates, fats, and proteins. Sodium Aids protein absorption and maintains ionic strength of body fluids. Comes with bolt holder to put on cage.