Restore health & vitality to dry & brittle hair with the Kérastase Masque Force Architecte. The rich formula of this mask has been specially formulated reconstruct hair that is in need of a little TLC to leave your locks smooth & soft. The intensely strengthening formula targets extremely dry & damaged hair to warp every strand in goodness & leave hair feeling revived & totally renewed. This product treats hair with an erosion level of 1-2. Directions of use: Apply 1 or 2 walnut-sized amounts to cleansed hair. Massage to lengths & ends. Leave on for 5 to 10 minutes.