Our vitamin C Serum is a "Bioactive" L Ascorbic Acid (LAA) Serum and not a Vitamin C Ester Serum such as Sodium Ascorbate or Ascorbyl Palmitate. There exists only 1 Vitamin C in the world and that is L Ascorbic Acid. Serums that do not contain L Ascorbic Acid are not vitamin C serums, they are merely Vitamin C derivatives. L Ascorbic (LAA) Acid is notorious for being not stable, and is very difficult to formulate. Many of the L Ascorbic Acid serums on the market are easily oxidized and lose their efficacy within 48 hours. Therefore, there are not many L Ascorbic Acid Serums on the market because they tend to lose their entire potency before they arrive to the shelves of stores. PURE LEAF BEAUTY , LLC succeeded in extending the stability of L. Ascorbic Acid for 12 months, using Triple C Technology, and Provides it fresh to you when ordered. Best Vitamin C Serum for face antioxidants are found within the serum that is able to reduce skin damage caused by air pollution and prolonged sun exposure. L Ascorbic Acid brightens the skin and immediately diminishes the appearance of fine line and wrinkles, and dark spots. It can also be used as a substance to help with your existing acne treatment. "Triple C" Technology Vitamin C Serum consists of 10% Ascorbic Acid (Vitamin C), (Vitamin C/ Kakadu-Plum), and .9% Acerbate (Vitamin C derivative); therefore, they sometimes call this formula "Triple C". These three (3) forms of Vitamin C's work in concert, and maximize the efficacy of L Ascorbic Acid.