ABN Spark Plug Thread Repair Kit, 14mm Reamer Cylinder Thread Repair Tool & Thread Insert &ndash; Spark Plug Rethreader Kit REPAIR PLUGS: The ABN Thread Repair Tool Kit is a time-saving kit that allows you to cut threads to fix a stripped and damaged 14mm spark plug threaded hole port and repair plug configurations in aluminum heads; Socket includes metal retainers to keep plug held inside during install and removal Includes ABN Tapping/VARIOUS APPLICATIONS: Chrome-vanadium steel (CR-V) M14 x 1.25 internal thread size on repair sleeve suitable for damaged spark plug threads to clean and rethread spark plug ports on a BMW vehicle and some Nissan and Toyota engines; As long as the head is aluminum and the spark plug hole is straight with room to turn the tap using either a ratchet or wrench, this kit will allow you to repair plugs without removing the head along with four inserts EASY TO USE: Rotate the crankshaft to make sure no ports/valves are open, use the tap to install new threads, choose the proper depth of insert, and screw it firmly into the newly tapped head; Apply grease on the tap to help catch any metal shavings (rather than letting them drop into the cylinder) and back out the tap out every half turn to every whole turn to clean the metal shavings from the tap; Grease recommended, not included PERFECT SIZE: 14mm reamer with 12 points; 2.5-inch overall length; Use with 3/8-inch drive ratchet or wrench; Inserts sizes are 3/8-Inch, 7/16-Inch, 1/2-Inch, and 3/4-Inch; Tap is tapered to allow the tip to fit and rethread the hole in order for the coil to fit; Measure your plug diameter, thread, and pitch to see if this kit is compatible PACKAGE CONTENTS: Rethread kit includes a tapping reamer and 4 different depths of inserts for your convenience Tapping reamer 4 inserts<ul class="a-unordered-list a-vertical"> 3/8-Inch 7/16-Inch 1/2-Inch3/4-Inch