Helicoil 4833 Oxygen Sensor Thread Repair Kit M 18 x 1.5 M 18 x 1.5 piloted reamer tap - no drilling necessary and insures perfect alignment of new tapped hole Corrosion resistant stainless steel inserts Eliminates costly exhaust manifold replacement when only the oxygen sensor hole is stripped Includes piloted reamer tap, installation tool and (6) inserts