Tsudo 08-12 Impreza STI 11-13 WRX 5dr 3in Quad-Tip Catback Exhaust v3 Manufactured from T304 / SUS304 stainless steel for durability and high corrosion resistance CNC machine mandrel-bent stainless steel tubing for maximum exhaust flow Significant weight reduction compared to OEM exhaust system Improves horsepower, torque, throttle response, and fuel mileage Includes all necessary hardware (bolts and gaskets) for Bolt-on installation with typical hand tools