This axle - back exhaust system is perfect for Mazda 3 owners who want to enhance their driving experience. Whether you're cruising on the highway or hitting the track, it will add a touch of style and performance. The target users are Mazda 3 enthusiasts looking for a reliable and easy - to - install exhaust upgrade. The tubing is 2 - 1/2 inches in diameter, and the exhaust tips have a 4 - inch diameter. Made from 304 stainless steel, it's built to last and withstand the rigors of daily driving and high - performance use.