Endura-max is an electrolyte supplement designed specifically for endurance horses. Contains calcium and magnesium. For preloading prior to the start of a competition, endura-max can be mixed with the grain portion of the diet. For immediate oral supplementation, mix endura-max in a syringe with water or another carrier such as applesauce or yogurt. Size is 40 Pound. Dimensions are 13 X 13 X 14.75 Salt (Sodium Chloride), Potassium Chloride, Dextrose, Calcium Acetate, Calcium Carbonate, Magnesium Oxide, Natural Flavors. UPC Code = 180434000071