Leathery dark brown seaweed, that can grow up to 3,5m in length, with a large holdfast that is cone-shaped. It has a broad, large and tough laminate blade to 1,5m long that is divided in straps or finger-like segments. The stipe is stiff, with a rough texture, thick at the base and tapers towards the frond, and it’s generally sticks up out of the water. The length of stipe varies with season, age and location of the plant.