CoverGirl & Olay Simply Ageless Serum Primer's moisturizers penetrate the epidermis (top layer of the skin), leaving a smooth base on your skin like a primer.; The lightweight, creamy formula goes on clear and is easy to apply with fingers across your whole face. It preps skin to help create a smooth canvas on which foundation can be applied.; Working under foundation to provide continuous hydration and moisturization, CoverGirl & Olay Simply Ageless Serum Primer is the only primer, formulated with the power of Olay Serum, to help firm the look of skin.; The formula contains ingredients from the amino-peptide complex that is used in the Olay Regenerist line, along with glucosamine, a key ingredient in the Olay Definity line.