Living Proof Full Thickening Mousse is an ultra lightweight mousse that provides flexible volume that lasts 5 times longer. It helps fine, flat hair to look and feel like naturally full, thick hair. By depositing a flexible, micropattern of thickening dots on each strand, this Mousse provides volume that lasts all day without collapsing or becoming stiff. Light hold; for fine hair. Sulfate-free, silicone free, oil-free; safe for color and chemically treated hair.