This serum is good for acne scars and pigmentation, brights skin and reverse solar damage, evening your skin tone. Diminishes red marks and pimples, and with 20% ascorbic acid concentration, is one of highest concentration serum. Price is really good for such quality, and quantity is enough for three or four months. You need to use it fast and keep it closed in dark, fresh places. Leaves a red tint on skin, but fades easily. The smell on your skin is kind of funny, like copper, but very tolerable. I´m very happy with results, makes your skin soft, even, and repaired from many types of damage. Will repurchase.