The Redken Extreme Length Shampoo 300ml with Biotin fortifies hair from the root to tip for 5x stronger hair.Redken Extreme Length Shampoo 300ml is perfect for anyone who wishes to grow their hair (even while colouring or bleaching!), especially those with naturally fragile or damaged and prone to breakage hair, who feel like their hair never grows past a certain length. Contains Biotin to help strengthen the hair causing less breakage and allowing the hair to grow longer. Redken Extreme Length Shampoo 300ml also helps prevent and reduce the look of split ends!