Tegiwa GT4 Style Full Pre Preg Carbon Fibre Front Splitter. Whether you’ll looking to hit the track, or perhaps add a more aggressive look to your M4, Tegiwa’s GT4 style lip ticks both boxes for form and function. This splitter comes complete with everything you need to fit it, making it entirely fit and forget. This product is also featured on Tegiwa’s M4 endurance car, providing additional downforce, as well as direct brake cooling thanks to the brake ducts included in the design.