Kerastase Resistance Serum Therapiste Dual Treatment for Extremely Damaged Lengths and Ends is an oil and cream based treatment that helps to coat, refill and restructure your hair fiber from within. Hair lengths and ends are left healthy, full o shine and soft to the touch. Kerastase Resistance Serum Therapiste Dual Treatment helps protect hair from heat styling and humidity. Can be used on both wet and dry hair for added shine, protection and damage control. Improves elasticity to help prevent breakage. Protects hair against heat of up to 450F. Helps reduce split ends by over 50%. How to use: Kerastase Resistance Serum Therapiste Dual Treatment is the final step of a 4-step Fiber renewal System. Begin by moisturizing hair and cleansing it with Kerastase Resistance Soin Premier Therapiste and Bain Therapiste. Once a week use Kerastase Masque Therapiste once a week for ultimate nourishing and protection. Complete your damage reversal by adding a small amount of Kerastase Resistance Serum Therapiste Dual Treatment to towel-dried hair from roots to ends. Style as usual.