OTOTEC M9 Thread Repair Kit M9 x 1.25m Metric Automotive Repair Tool SetFit for engine repair and other automotive applications, for steel, cast iron and aluminum, for restoring damaged or worn out threads. Made of high speed steel material, high wear resistance, good toughness, sturdy and durable in use,has a long service life. First, drill out damaged thread using correctly sized drill bit(supplied). Tap re drilled hole using tap supplied. Then, load coiled insert into applicator. Screw coil into casting, Last,using lug