Replaces Stripped Spark Plug Threads On Ford V10, 4.6 And 5.4 Liter Engines. This precision tool accurately replaces stripped Ford spark plug threads with new thread inserts. Works on the car without removing the engine head. This set includes a drill, tap, swedge tool, insert tool, 10 steel inserts, plus a vacuum adapter to remove shavings from the chamber. The tool set installs a new spark plug thread insert in the exact original position in approximately 20 minutes.IMPORTANT: An inspection scope must be used to insure all shavings are removed from the combustion chamber. An inspection scope is not included in the 65900 set. 65960 Thread Insert is available individually. Loctite 7649 Primer and Loctite 272 Threadlocker may be used in place of the primer and sealant included in the 65900 set.