Kiehls original anti-ageing Vitamin C serum, Powerful-Strength Line-Reducing Concentrate, now with 12.5% Vitamin C and Hyaluronic Acid.Now formulated with even more Vitamin C, Dermatologist Solutions Powerful-Strength Line-Reducing Concentrate incorporates 10.5% L-Ascorbic Acid and 2% Ascorbyl Glucoside. In addition to Vitamin C, this anti-ageing serum now includes Hyaluronic Acid. The formula helps reduce the appearance of lines and wrinkles while helping to improve the feel of skins texture. Skin looks radiant and feels smoother. This Vitamin C serum is carefully-formulated to provide clinically-proven results in a concentration gentle enough for sensitive skin.