A high strength and stable vitamin C serum to help combat sun-induced damage to the skin and maintain collagen production, increase the skin’s elasticity and density, as well as improve the skin’s texture and brighten the complexion. Contains higher strength of lipid soluble Vitamin C for enhanced penetration and stability. CE-Tetra contains vitamin E which synergistically boosts the overall antioxidant effect. A higher (more than double) level of vitamin C is included in CE-Tetra formula compared with C-Tetra. This formula is for people at any age who are seeking a higher strength vitamin C serum, and ideal for people in their 40's or above.