This is the equivalent of serum for your skin. Like SST's Hyaluronic Serum that delves to the bottom layers of your skin to deliver and hold moisture, the Replumping shampoo does the same for every hair shaft. The Replumping products are referred to as "hair filler" superactives, because they do just that. They fill areas lacking in moisture. A lovely side effect is improved elasticity, which means it makes your hair stronger. And if that's not enough to impress you, Davines has chosen an essential oil as fragrance for the Replumping products that ALSO has compacting properties!