Polished cold air intakes systems Cold Air Relocates the filter outside of the engine compartment to deliver the coolest air inlet temperatures possible, which creates more horsepower and torque SUBARU Impreza WRX / STi / TR 2.5L 2008-2010AEM Air Intakes are engineered to add horsepower and reduce restriction compared to OEM air intakes. All AEM Air Intakes come with a lifetime DRYFLOW Synthetic air filter with great filtration. AEM Air Intake Systems including our Cold Air Intake, Short Ram Air Intake, and Brute Force Air Intake Systems are guaranteed for the life of your car or truck. Manufactured in the USA.2011 SUBARU IMPREZA WRX STI 2.5L H4 F/I - All Street Legal In All US States: No 2011 SUBARU IMPREZA WRX 2.5L H4 F/I - All Street Legal In All US States: No 2010 SUBARU IMPREZA WRX STI 2.5L H4 F/I - All Street Legal In All US States: No 2010 SUBARU IMPREZA WRX 2.5L H4 F/I - All Street Legal In All US States: No 2009 SUBARU IMPREZA WRX STI 2.5L H4 F/I - All Street Legal In All US States: No 2009 SUBARU IMPREZA WRX 2.5L H4 F/I - All Street Legal In All US States: No 2008 SUBARU IMPREZA WRX STI 2.5L H4 F/I - All Street Legal In All US States: Yes CARB EO Number: D-670 2008 SUBARU IMPREZA WRX 2.5L H4 F/I - All Street Legal In All US States: Yes CARB EO Number: D-670