The Metal DX PreShampoo from L'Oréal Professionnel Paris is designed for all hair types and protects the hair when it is most vulnerable to metals in the water: BEFORE shampooing. Metals present in the water, such as copper, can penetrate the hair during washing and cause hair breakage and color changes. Enriched with 2% Glycofiller, the PreShampoo fills microcracks in the hair in just one minute thanks to the AntiPorosity Technology and simultaneously coats the hair fiber from the outside. The result: the hair is less porous, stronger, and intensely moisturized. In just one application: 96% less hair breakage and hair 25 times stronger. 72h moisture and smoothness. *Instrumental test. **Instrumental test: after 10 applications of Metal DX PreShampoo Shampoo Mask Oil.