Redken Acidic Perfecting Concentrate Leave-in Treatment provides heat protection up to 230 degrees, smoothes, tames frizz, adds shine and intensely conditions to help to reduce hair breakage. This pH-balancing leave-in Treatment is specifically formulated with an acidic pH to help to defend against the potential negative effects that can be caused by hair colouring, lightening and heat styling. The result? Hair that looks and feels healthy! To use: Use as a complete system with Acidic Bonding Concentrate Shampoo and Conditioner. Apply to clean, damp hair. Leave in. Do not rinse. Style as usual. Avoid contact with eyes.