Gluten Free. Naturally Sweetened. Kill Cliff was developed by a former U.S. Navy Seal – as an athletic performance product. It can improve endurance and speed recovery. Kill Cliff is made from the highest quality ingredients available and may help you perform at a higher level for a prolonged period of time. Kill Cliff is low calorie and lightly caffeinated, with a natural blood-orange flavor. Kill Cliff is a refreshing alternative product and it tastes great. A portion of the proceeds from every case sold is donated to Navy Seals and special operations related charities.