This Duraflex M4 look rear diffuser is perfect for car enthusiasts who want to enhance the look of their 2014 - 2020 BMW 4 Series. Whether you're driving on the city streets or hitting the track, it adds a touch of sportiness. The diffuser is made of FRP material, which is strong and durable. It comes as a single piece (S) and must be used with an M4 look rear bumper. Remember, professional installation is needed to get the best results.