Product Description Redken’s Extreme Length Leave-In Treatment with biotin strengthens damaged hair and helps hair to grow longer and stronger. Extreme Length Leave-In Treatment helps prevent breakage to promote your strongest, healthiest hair. Fortifies and strengthens hair for 81% less breakage* 5x stronger hair Promotes healthy, stronger hair from root to tip * Extreme Length Shampoo + Conditioner + Leave-in Treatment versus non-conditioning shampoo