This unit is made out of 304 stainless steel with a high quality merge collector, big 1 1/2" primaries and the correct 1 7/8" outlet flange as the factory header utilizes. It is completely TIG welded and back purged. It also has the two O2 sensor bungs just like the factory unit. Unlike other companies headers this header will actually make power while the competitors has been proven lose power. This header is fully compatible with SFR Turbo Kits.