Fitment Information Subaru WRX & WRX STi (2002, 2003, 2004, 2005, 2006, 2007) Emissions Information This is a catback exhaust and does not alter, remove or replace any emissions equipment. Specs & Features 76mm Catback Exhaust Noresonator 101mm Exhaust Tip The Invidia N1 exhaust system is designed to offer you the ultimate in exhaust flow and performance. Engineered to increase horsepower and torque, the Inividia N1 exhaust has aggressive sound due to it's ultra high flow N1 style mufflers with the unique Invidia sound that enthusiasts love. Designed to improved mid to top end power and offers enough exhaust flow for a stock to heavily modified vehicle. Invidia N1 Exhaust Features: Top quality SUS304 Stainless Steel Exhaust CNC Machined Flanges for perfect fitment Mandrel stainless steel exhaust piping for max flow and reduced back pressure Straight through mufflers for ultimate performance Strong mid to top end power Legendary Invidia sound and quality Bolt on exhaust and includes all necessary bolts, gaskets and hardware