The Kiehl's Since 1851 Micro-Dose Anti-Aging Retinol Serum is a potent serum in a daily-strength micro-dose that visibly reduces wrinkles, firms skin, and evens texture and tone with minimal discomfort. Key Ingredients Pure Retinol: helps steadily accelerate skin surface turnover to bring new, fresh skin to the surface to help address visible signs of aging Ceramides: help strengthen the moisture barrier to enhance skins tolerance of pure retinol Peptide: works to enhance skin integrity, helping it receive optimal, visible youth-renewing results How To Use After cleansing, apply one pump of Kiehl's facial serum with Retinol over the entire face, including the under eye and crow's feet area, carefully avoiding contact with the eye and eye lid area. If applied during the day, Kiehl's serum with retinol should always be used with SPF. Can be used daily, in the morning or at night 1.0 fl. oz.