Brand from United States: Kiehl's. Now formulated with even more vitamin C, Dermatologist Solutions Powerful-Strength Line-Reducing Concentrate from Kiehl’s incorporates 10.5% L-Ascorbic Acid and 2% Ascorbyl Glucoside.In addition to 12.5% 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.How to use:Apply over entire face twice morning and night (avoiding the eye area).In case of contact with eyes, rinse them immediately.As the formula blends into the skin, you may experience a feeling of warmth.