Explosive energy, increased focus, and an overwhelming need to face any challenge... That's the c15 experience. But with two package sizes and various delicious flavor options for you to choose from, you'll feel the difference that c4 makes during your workout. Contains carnosyn(r) beta alanine. C4 will help you reach your maximum potential. Whether you're just starting a fitness journey or striving to reach the next level, the c4 pre-workout shake will help you unleash your full potential.