Refresh and protect colour with the Redken Acidic Color Gloss Duo. This set includes a 300ml Acidic Color Gloss Sulphate-Free Shampoo and a 300ml Acidic Color Gloss Conditioner formulated for colour-treated hair. The advanced pH formula and Acidic Shine Complex help deliver a glass-like gloss for up to 3 days when used as a full system (consumer test). The sulphate-free shampoo gently cleanses while preserving colour. The conditioner boosts moisture, smooths each strand and locks in colour, delivering +76% glass-like shine in consumer testing when used as a full system. Citric acid rebalances hair to pH 4.5–5.5, sealing the cuticle to help protect against external factors that contribute to colour fade. Consumer testing shows hair feels hydrated and nourished for up to 72 hours after a single use of the shampoo and conditioner system. How to use: apply shampoo to wet hair, lather and rinse. Apply conditioner to mid-lengths and ends, then rinse.