SkinCeuticals Serum 20 AOX (30ml) Formulated at the precise concentration proven to deliver maximum amounts of vitamin C to the skin, Serum 20 is now formulated with AOX+ advanced antioxidant technology, combining ferulic acid with 20% L ascorbic acid to enhance antioxidant performance. Designed to restore and protect healthy looking skin, this lightweight and fast absorbing serum neutralizes free radicals, defends against environmental damage, and helps prevent premature signs of aging. Ideal for normal to oily skin. Benefits: AOX+ advanced antioxidant technology combines ferulic acid with L ascorbic acid to enhance antioxidant performance Reduces the appearance of fine lines and wrinkles, neutralizes free radicals, defends against environmental damage, and stimulates collagen synthesis Using Duke patented vitamin C technology, delivers 20% L ascorbic acid to the skin highest level effectively absorbed Once absorbed it can not be washed or rubbed off, remaining protective for up to four days an excellent addition to sunscreens Ideal for normal or oily skin