(Vita Flex Nutrition) Pure C Premium Quality Vitamin C for Horses is a concentrated supply of vitamin C, an important anti-stress nutrient and crucial co-factor in connective tissue maintenance and repair, immune function, and hundreds of other physiological processes. Vitamin C has rightly been called "the workhorse of the vitamins". Pure C is 98% ascorbic acid - it's the most economical way to give your horse this vital nutrient. Feed 1/4 oz. daily for maintenance, or 1/4 oz. twice daily, during periods of illness or extreme stress. 1/4 oz. measure included.