K18 Leave-In Molecular Repair Mask is a progressive treatment that repairs, strengthens, and improves the hairs elasticity in just 4 minutes. This easy to use Leave-in Repair Mask reverses damaged and compromised hair while it softens and detangles. The K18 does not wash out when shampooing your hair it is long lasting to help your hair be protected from every day exposure including styling, colouring and lightening. Patented with bioactive peptides that repairs keratin within the hair cuticle, ultimately gives you noticeable affects making your hair stronger, softer for a more manageable.