Insure fuel quality during storage. Increase gasoline octane or diesel cetane. Improve engine performance (horsepower and torque). Improve fuel economy. Reduce emissions - green house gases. Reduce engine maintenance. Improve oil burner efficiency. One application good for 250,000 miles or 5000 operating hours. Sold two capsules per display card. One capsule is good for up to a 10 gal tank.