The ARK downpipe and test pipe are designed to get the most uut of high revving race motors. We use 2.5" Piping SUS-304 Steel, Increases dyno proven Horsepower And Torque From Mid-Range To Redline. The ARK "H" Pipe Test Pipe is designed to delete your secondary cats. With the H-pipe design, it helps reduce the hissing/rasp noise around 3,000-2,000 RPMs. Our test pipes will bolt directly to your OEM Stock Factory Exhaust and/or any aftermarket catback exhaust with OEM fitment only. ARK Advantages and Features: - All Bolt-on System - SUS304 Stainless Steel Construction - Fully Polished Finish, 2.5 inch Piping - CNC Machined Flanges - Exposed Micro TIG Welding Items Included: Test Pipe, Bolts, Gaskets, Hardware, Installation Guide *For all orders shipped outside the U.S. tax/duty/custom fees are not included