Our exfoliating toner sloughs away the top layers of dead skin cells that can make your complexion look and feel dull, dry and rough. This allows new cells to come to the surface leaving your skin looking fresh, plump and glowing. We indicate our toner's low-ph level as 3 because the lower the pH, the more active the Glycolic Acid and the more effectively it can penetrate the skin. Glycolic acid needs to be in its most active form to penetrate the skin’s oily outer barrier. This is why you may feel a slight tingle on application.