Kérastase Resistance Concentre Vita-Topseal Intensive Refinishing Treatment for Weakened Hair Technology: Vita-Topseal is a refinishing ingredient that mimics the external natural protective layer of the hair and reinforces teh internal substance of the hair fibre. The surface of the fibre is strngthened. The fibre is cated with a topseal protective film. Helps restore suppleness, movement and shine the hair