#1 Shampoo in Prestige Haircare* A highly-nourishing and reparative shampoo. N°4 Shampoo repairs and protects hair from everyday stresses — including damaged hair, split ends, and frizz — by re-linking broken bonds. Leaves hair easier to manage, shinier and healthier with each use. N°4 is color-safe and proven to reduce breakage and strengthen all types of hair. PH Balance: 6-6.5