Flowmaster's American Thunder Axle-back exhaust system for the 2015-2020 Ford Mustang with the 2.3L Ecoboost and 3.7L engines is perfect for the person looking for a moderately aggressive sound level outside of the car while maintaining a mild sound level inside. This bolt-on emissions-legal system for cars features 3.00 in. mandrel-bent inlet pipes flowing into a pair of Super 10 Series mufflers for maximum performance. The system is constructed out of 409S stainless steel for durability, is finished off with large 4.00 in. polished stainless steel tips and is covered by our Lifetime Limited Warranty. Designed for an easy fit, this system includes all necessary parts and hardware for installation. Note: The sound level of this system is quieted by the factory resonators. Check out our Resonator Delete kit part 81107 and 81108, if you desire more sound from your Ecoboost or 3.7L engine.