Cot Rehau Rautitan Ø25-90° Rehau Rautitan Ø25-90° is a type of pipe fitting used in plumbing systems. It is used to connect two pipes at a 90-degree angle. It is made from polypropylene, making it strong and durable. It is also resistant to corrosion and other forms of damage. The fitting is also easy to install and can be used with a variety of pipe sizes.