These 981 RS Vented Carbon fenders are made by the same manufacturer that supplies Porsche Motorsports with a number of 997 and 991 Cup car body parts. The fitment is factory and will require professional autobody installation. Fenders fit all 981 Cayman and Boxsters through the GT4/Spyder. Reduce lift in the front of your 991.2 GT3 or GT3RS and aid in turn in grip! These Dual Dive Planes were designed with Computational Fluid Dynamics to aid in shape in placement and are part of our complete Aerodynamic upgrade package for the 991.2 GT3 and GT3RS. Fenders are made to order, please allow 3-4 weeks for delivery.