Primes hair to absorb nourishment for maximum repair.A professional-inspired treatment that primes hair for deeper repair with the highest dose of patented OLAPLEX technology in any take-home product. It rebuilds hair bonds and strengthens and protects hair integrity. Use as the first step in a two-part system with N°3 Hair Perfector.  

Scientifically Proven: 68% more repair & 3x stronger hair* 

OLAPLEX products are thoroughly tested in-house and by independent third-party laboratories for safety and efficacy. This product testing includes the industry standard Human Repeat Insult Patch Test (HRIPT), which tests for skin irritation or sensitivity. All of OLAPLEX products passed the HRIPT, meaning the products show no signs of causing irritation, inflammation, or sensitivity. 

5.2 fl oz / 155 ml