This leave-in serum forms the fourth and final step in the new Bond Repair haircare routine for stronger hair with maximum shine and heat protection. Hair is made up of millions of bonds that give it structure and strength. When hair bonds break, through brushing, bleaching, heating, and styling, hair becomes weak and damaged. For the first time, our formula powered by Citric Acid Complex targets damaged hair. Up to 12x less split-ends¹, 98% stronger hair² & 82% more shine². Suitable for all types of damaged hair.