As with all of OLAPLEX’s hair heroes, the star ingredient in this weightless, silicone-free serum is bis-aminopropyl diglycol dimaleate. That might sound a bit science-y but this bond-building technology will restore and repair chemical-treated, heat-ridden hair, leaving it full of shine, soft to the touch and so much easier to style. Slotting into your routine as the first leave-in treatment on clean tresses, this serum protects from future damage too, as it’s packed with antioxidants to neutralise free radicals, act as a shield against pollution, guard your hair from breakage and protect against heat styling.