Use this exhaust system when you want to enhance your Toyota 4Runner's style and performance, whether you're on city streets or off - road adventures. It's perfect for 4Runner owners who love to make their vehicle stand out and are looking for a reliable upgrade. The system has a 2.5 - inch cat - back exhaust with a 4 - inch outer diameter tip and is made of heavy - gauge aluminized steel tubing, offering great durability in dry climates.