This ultra-light volumizing shampoo is specially formulated for fine hair and is clinically proven to strengthen, repair, and protect against future damage caused by daily stressors, styling, and salon treatments.* The ideal shampoo for fine hair should not only add volume but also restore health. Nº. 4FINE gently eliminates buildup, leaving hair clean, soft, and full of long-lasting volume, body, and bounce, without ever feeling heavy or dried out.