L'Oréal Professionnel Dia Light is an ammonia-free, semi-permanent, tone-on-tone hair colour designed for maximum shine and conditioning. It's ideal for hair that has been previously coloured, weakened, or sensitised, serving as the perfect partner for colour refreshes and toning lengths and ends between regular colour services. The acidic gel-cream technology neutralises and adds gloss after lightening and refreshes lengths after colour. Dia Light's ammonia-free formula seals the cuticle for a vinyl-like finish, making it excellent for previously coloured hair. The Dia Light Boosters are perfect for colour refreshes and toning, and when mixed with Dia Light, the Ash Booster allows for infinite possibilities and personalised results. This booster helps enhance neutralisation and visibility for reflects on darker bases, creating bronzed glossy lengths to stay on-trend. Experience rebalanced, healthier, nourished, and glossier hair with this unique formula.