STILLEN 504385 Stainless Steel Cat-Back Exhaust System - 03-08 FX35 / FX45 (03-08 RWD / 03-05 AWD) 304 Stainless Steel Construction Polished 304SS Dual Wall Tips Increase of Horsepower and Torque Mild at Idle/Cruising - Aggressive Note Under Throttle; Limited Lifetime Warranty