For Nissan 200SX/NX/Sentra 4-2-1 Design Stainless Steel Exhaust Header Kit - 2.0L Made of high quality steel with 4-2-1 direct bolt-on design TIG welded CNC machine flange O2 sensor and EGR bung insertion / Metal gasket included / Inlet: 2" / Outlet: 2.5" Increase high flow air, instantly gain 10 to 15 Hp. / Tq Application: Please check part finder on top of the page (Professional Installer is Highly Recommended) (No Instruction Included)