Olaplex No.0 Intensive Bond Building Hair Treatment - 5.2oz is a professional-inspired, pre-shampoo treatment designed to prime hair for deeper repair. Powered by patented OLAPLEX Bond Building Technology™, this lightweight formula works to rebuild broken bonds, strengthen the hair structure, and boost the performance of No.3 Hair Perfector. Ideal for all hair types, it provides intensive repair, improves softness and resilience, and is the first step in a powerful two-part at-home treatment for visibly healthier hair.