MDPE reducers are used to connect two different sizes of MDPE together, i.e. 25mm to 20mm.Made from tough and long-lasting polypropylene, our MDPE fittings utilise an acetal grip ring and a Nitrile rubber O ring.Pipe liners (or stiffeners as they are sometimes called) should always be used with this type of fitting to strengthen the pipe wall when the connection is made.This fitting is WRAS approved. All of our MDPE fittings can be used on either blue (potable) MDPE pipe or black (non-potable) MDPE pipe.