Phyto Phytokératine Extrême, 100 ml, Hair Creams and Gels for Women, The Phyto Phytokératine Extrême leave-in treatment gives your hair everything it needs after washing. Characteristics: has regenerative effects increases the thickness and strength of hair gives an appealing shine provides hydration and nourishment for your hair How to use: Apply to towel-dried hair. Do not rinse.