Give your hair colour a boost of vibrancy and up to six more weeks of freshness. As with all Soma shampoos, the pH range is between 4.5 to 5.5 to guarantee that your hair cuticle remains closed - locking in colour. This Sulfate-Free shampoo helps to detoxify your hair while providing organic based proteins to ensure a healthy post-colour recovery. (16 oz) Highest Quality Shampoo available.