This supercharged Vitamin C treatment includes a powerful antioxidant effect that is developed to provide optimum protection from free radicals, boost skin glow, and target imperfections from photoaging. Use this product if you are looking for visibly brighter, smoother, firmer and younger-looking skin. In this formula we use three different types of Vitamin C. Why, you might ask? The answer is very simple: because the function of Vitamin C varies within the different layers of the skin, we use the necessary type of Vitamin C when and where it is needed. There are many types of Vitamin C for skin care applications, and we have selected the most stable and pure to ensure it’s effectiveness within all layers of the skin. Need an explanation? Here you have it: C-TETRA E.F. has been formulated with 10% Vitamin C Tetra, which is highly biocompatible and liposoluble. The fact that it is liposoluble allows this type of Vitamin C to be transported down into the deepest layers of the skin. Here, its action is focused on melanocytes (to treat blemishes from the inside) and on collagen synthesis (to prevent and fight wrinkles from the inside). The formula is complemented by Ascorbosilane and Ascorbyl Glucoside, two very stable and water-soluble Vitamin C derivatives. They act on the surface of the skin to improve skin glow and reduce the most common blemishes. The formula is complemented with Vitamin E and Ferulic Acid, the award winning combination that boosts the serum's total antioxidant effect to keep your skin protected, all day long.