C-Strength contains a stable and effective blend of vitamins C and E to strengthen and brighten the skin, as well as diminish fine lines and wrinkles. This powerful formula pairs 15% vitamin C with 5% vitamin E, the optimal amounts for topical absorption, to create this gentle, nourishing formula. Suitable for all skin types, including sensitive and easily irritated skin. Use day and night for maximum skin renewal. Ideal for use on the face, hands and chest. C-Strength 15% is best for sensitive skin or first time vitamin C users. For acclimated skin, try C-Strength 20%.