What it Does Our professional-inspired treatment primes your hair for deeper repair, rebuilds hair bonds, strengthens, and protects hair integrity. Use as the first step in a two-part at-home system with No.3 Hair Perfector (sold separately) to strengthen and repair all types of damaged hair. Redesigned for a quick and targeted stream application, the No.0 Intensive Bond Building Hair Treatment features an easy to use nozzle that primes the hair and delivers the highest concentration of the patented bond building technology of any Olaplex at home product. Scientifically Proven: 68% more repair & 3x stronger hair* *When used as a two-part system in just one use. APPLICATION TIP: No.0 bottle should last 3-6 applications, based on hair length and density. How to Use Apply slowly to dry hair, distributing evenly from root to tip. Work No.0 into small sections by squeezing the liquid into the hair to be fully absorbed as you go. Lightly saturate from root to tip. Hair should be damp, not drenched. Let process for 10 minutes. DO NOT RINSE. Apply No.3 Hair Perfector over hair with No.0 applied to it, combing through as needed. Let process for a minimum of 10 minutes. Rinse, shampoo & condition. For best results, use No.4 Shampoo & No.5 Conditioner. Hair Type: Coily, Textured, Wavy, Curly Fluid Ounces: 5.2 oz. Country of Origin: Made in US Ingredients: Water (Aqua/Eau), Bis-Aminopropyl Diglycol Dimaleate, Phenoxyethanol, Sodium Benzoate