The K18 Molecular Repair Mask is a leave-in treatment that reverses hair damage in just 4 minutes using the patented K18Peptide™. It works on a molecular level to restore strength, elasticity, and smoothness—without rinsing or buildup. This 15 ml size is perfect for maintaining healthy, resilient hair at home between salon visits. Just one application leaves hair visibly healthier, softer, and stronger.