Olaplex No. 0 Intensive Bond Building Treatment is a professional-inspired at-home priming treatment that repairs and strengthens hair bonds from within. It is designed to work as the first step in a two-part system to intensely repair broken bonds caused by chemical services, heat styling, and mechanical or thermal damage. This intensive formula prepares the hair to maximize the benefits of the subsequent Olaplex No. 3 treatment, leading to visibly healthier, stronger hair. Regular use helps restore the integrity and structure of the hair fiber.