The Cobb Tuning catless uppipe is constructed of rugged, 14-gauge, 2-inch diameter polished stainless steel tubing to endure the intense exhaust gas temperatures from your modified Subie. The uppipes are CNC mandrel bent, ensuring precise and consistent fitment, eliminating the need for a weak flex joint section. The inlet diameter matches the inner diameter of the gasket to maximize flow to the turbo and minimize gasket failure. The extra-thick flanges are cut from 1/2" 304 stainless steel to prevent warping and eliminate high pressure exhaust leaks. The five turbo-flange studs come pre-installed. This gorgeous uppipe is built to last for many long years of service.