Stainless Steel Manifold Header/Exhaust For 1997-2005 Subaru Impreza 2.5LRS EJ25 NA Made Out Of High Quality Stainless Steel,Inlet/ Outlet: 1.50"/ 2.00",O2 Sensor Insertion and Metal Gasket Included.TIG Welded CNC Machine Flange Increase High Flow Air, Instantly Gain 10 -15 Hp. / Tq.Intended For Racing Or Off Road Use Only Fit for 97-05 Subaru Impreza RS 2.5L Non-Turbo Professional Installation is Highly Recommended No Instruction and Wiring Diagram Included