benefits of using the Keratin Biotin Pure Sulfate Free Hair Mask: Repairs damaged hair Prevents breakage Promotes hair growth Moisturizes and nourishes hair Leaves hair feeling soft and healthy The Keratin Biotin Pure Sulfate Free Hair Mask is a good option for people with damaged hair, hair loss problems, or dry, unhealthy hair. It is also a good option for people who are looking for a hair mask that is sulfate-free and free using the Keratin Biotin Pure Sulfate Free Hair Mask: Apply it to wet hair after shampooing. Leave it on for 5-10 minutes. Rinse it out thoroughly. Use it once or twice a week, depending on the condition of your hair. Smoothing/Straightening, Clarifying/Deep Cleansing,