These covers are just what you need to make sure no damage is done to the EGR plug when it is left disconnected after the EGR system is removed. Caps fit all cars with the FA20DIT Engine including the 2015+WRX and 2014-2018 Forester XT . These plugs are the same as what is built into the end of the factory EGR Valve. The holes in the end of the plugs are capped with clear silicone plugs that create a nice water tight seal as there would be when connected to factory parts. We also include a zip tie to properly secure the EGR plug harness section so that it doesn’t bounce around and possibly create false knock signals while driving.