Redken Extreme Length Shampoo with Biotin 300 mlBiotin Extreme Length Shampoo strengthens damaged hair and promotes hair growth. Gently cleanses hair and helps prevent damage. It heals split ends and restores the inner texture of the hair. Features: biotin shampoo ideal for long and damaged hair, gently washes and cleans the hair, supports their growth, helps prevent damage, heals split ends, restores hair texture. How to use Apply the shampoo to wet hair, lather and then rinse.