The Vichy Dercos Collagen Filler 17 Deep Repair Shampoo for brittle hair is a specialized hair care formulation designed to treat hair brittleness and breakage. This 200 ml shampoo contains the Collagen Peptide 17 System, which addresses weakened bonds in the hair fibers. Clinical studies show a reduction in hair breakage of up to 73 percent. The formulation includes collagen peptides to strengthen hair structure and promote regeneration, as well as citric acid, which penetrates the hair cortex to repair weakened bonds. This sulfate-free shampoo is suitable for all hair types and scalp conditions, working from root to tip to increase hair resilience and restore weakened hair due to collagen loss. It visibly improves hair fullness, shine, and density while caring for the scalp. For optimal results, it is recommended to use it as part of the complete three-step routine with the corresponding pre-shampoo and conditioner from the same product line. Apply directly to wet hair that has been pre-treated with the appropriate pre-shampoo, thoroughly massage into the scalp and hair lengths, and rinse completely before proceeding with the conditioner.