Grimmspeed StealthBox Cold Air Intake Red For Subaru 15-21 WRX GrimmSpeedGRM 060067 Inspiration for the StealthBox Intake came from internal discussions about what we wanted from an intake system for the 2015 21 Subaru WRX. Of course performance is the highest priority, but at GrimmSpeed so much more than that goes into a product. We wanted an intake that purred quietly under normal driving circumstances, but would roar at wide open throttle. We wanted an intake that looked at home in the well sported 2015 21 WRX engine