This Corsa 3" Axle-Back with a dual rear exit is designed for an aggressive sound under acceleration and a drone-free experience during cruise. This axle-back exhaust system is constructed from premium stainless steel to deliver lasting performance, sound and appearance. The Xtreme Series Axle-Back Exhaust gives you aggressive sound that is deep, bold at idle and throaty under acceleration. Note: This axle-back exhaust system fits the 2011-2013 Boss 302 Mustang. Product Features +7 horsepower gain 153% flow increase over stock 20lbs weight reduction +4 torque gain