Redken Acidic Bonding Concentrate Sulfate-Free Bonding Shampoo is Redken’s most concentrated all-in-one formula for strength repair on all types of damaged hair. This ultra-rich and luxurious shampoo provides ultimate strength repair, intense conditioning and color fade protection. Featuring Citric Acid, our Acidic Bonding Concentrate shampoo contains a concentrated bonding care complex that reinforces weakened bonds within your hair to improve hair strength. This pH-balancing shampoo is specifically formulated with an acidic pH to defend against the negative effects of hair coloring, heat styling tools, and even water. The result? Hair that looks and feels healthy!