Borla's unequal length header is here to unleash the Boxer rumble that your stock Subaru BRZ/Scion FR-S system does not produce. You can expect an increase in low end torque and throttle response throughout the RPM range. Every FR-S/BRZ Borla header is constructed from T-304 stainless steel to give you the best in performance and durability. The header is designed without the restrictive primary catalytic converter and the incorporated proven flex-coupler design combats the vibration of the Boxer engine for increased longevity. Borla products are backed by a million-mile warranty, so this is the only header you will ever have to buy for your BRZ/FR-S.