This vortex generator fits all 2017 WRX models with 7 inch Starlink Radios (with or without navigation) and ALL 2017 STIs (with or without navigation). 

• 2017-2021 WRX Premium with OPTIONAL 7" Starlink Radio
• 2017-2021 WRX Limited
• 2017-2021 STI

APR Vortex Generators help to guide the air flow on cars with very steep drop-off angles between the roof and the rear window. Air flow has a tendency to become turbulent as it separates from the surface of the car in this region. This turbulent air causes drag and reduces the effectiveness of a rear wing. The APR Vortex Generator helps to reduce drag and improve the effectiveness of the rear wing by delaying the air flow separation and reducing turbulence.