K18 Full-Size Leave-In Molecular Hair Mask, Repairs Dry or Damaged Hair, Reverse Hair Damage from Bleach, Color, Chemical Services & HeatBrand: K18 Features: An At home Leave In Treatment infused with the patented K18Peptide that renews hair to its most youthful, healthy state. Benefits: Works to repair even the most extreme damage caused by bleach and color, chemical services, and heat. Creates Like Hair Like New: Traveling into the inner most layers of hair to reach the core polypeptide chains our revolutionary K18Peptide is just the right size and makeup to reconnect broken chains