New Old Stock Heli-Coil M10 10-1.0mm Spark Plug Thread Repair Kit 5523-10 USA made

New Old Stock Heli-Coil M10 10-1.0mm Spark Plug Thread Repair Kit No.5523-10 . Premium quality USA made. This set is designed to permanently restore stripped or damaged M10x1.0 spark plug threads in engine cylinder heads Includes -24 Heli-Coil Stainless Steel Inserts -Heli-Coil Piloted Tap -Heli-Coil Insertion Tool ( has some light surface oxidation from years of storage ) NOT for tapered seat spark plug ports