For 05-10 Chevy Cobalt Catback Exhaust System 3.5" Burn Tip Muffler - LS LT LTZ 2.2L Made of High Quality T-304 Stainless Steel with Computerized Mandrel-Bends for Strength and Durability Dyno Proven to Instantly Increases 10-20 Horsepower/ Low End Torque TIG Welded CNC Machine Flange for Resistance against Pressure and Corrosion Aggressive Deep Sound while Ensures Smooth Exhaust Gas Flow; Increase Engine Output and Efficiency 3.5"(OD) Muffler Exhaust Tip; Inlet: 2.25"; Main Piping Diameter: 2.25"