ProMaxx Toolâ??s exclusive screw-in bushings, which incorporate proprietary mating angles that once seated, bring the bushing into perfect alignment with the cylinder head. Resulting in the most accurate and precise tool in the market. There's no need to fire up your welder. No matter the depth of the broken bolt, the Myraâ?? ProKit assures unmatched accuracy and productivity in drilling-out damaged exhaust manifold mounting studs on the 3.7L and 4.7L Dodge cylinder head. ProMaxx Toolâ??s exclusive screw-in bushings, which incorporate proprietary mating angles that once seated, bring the bushing into perfect alignment with the cylinder head. Resulting in the most accurate and precise tool in the market. Other kits use inexpensive clamps or loose slip-fit bushings. Bolting the Myra jig in any position with our included precision fasteners provides unparalleled repeatable and predictable results. Received a previous repair attempt or botched repair? No Problem. ProMaxx Toolâ??s larger plate holes provide thea thread repair kit that includes bushings, bits, and solid steel inserts to completely restore the cylinder head to factory condition. CERTIFIED YEARS, MAKES, MODELS 1999â??2009 Jeep Grand Cherokee 2000â??2007 Dodge Dakota 2000â??2009 Dodge Durango 2002â??2007 Dodge Ram 1500 2006â??2009 Jeep Commander 2007â??2009 Ch