Used by professionals. With Keratin Protein. Reduces breakage. TRESemme Total Strength is a professional solution for keeping hair stronger and healthier looking. Replenishing Shampoo & Conditioner System: Protects and replenishes weak, brittle and damaged hair. Professionally formulated with natural keratin protein. Reduces breakage and splitting by 60%. Keeps hair looking and feeling stronger and healthier. This product is not tested on animals.