Flowmaster's American Thunder cat-back exhaust system for the 2013-2018 Ford Focus ST hatchback is perfect for the person looking for moderate to aggressive sound levels with all of the performance benefits that you would expect from Flowmaster. This bolt on Dual Out Rear emissions legal system for the 2.0L L4 turbocharged engine features a specially tuned muffler and resonator, 2.25 inch mandrel bent stainless steel tubing, and 3.25 x 3.75 inch oval polished stainless steel tips. The exhaust system is covered by Flowmaster's Lifetime Limited Warranty. Designed for an easy fit, this system includes all necessary parts and hardware for installation.