Features and Benefits: Patented lip makes sure there is no loss of compression Permanent fix to damaged Cylinder threads Replacement insert for the MTN9200 repair kit Replacement spark plug insert for Ford engines Used to repair damaged cylinder heads with blown spark plugs Used to repair damaged cylinderheads with blown spark plugs this replacement insert has a patented lip to makesure there is no loss of compression. It is a permanent fix to damaged cylinderthreads. Replacing the insert for the MTN9200 repair kit. Specifically made forFord engines.