Car Spark Plug Tester Diagnostic Tool Dual Hole Engine Ignition Analyzer Tester

Spark Plug Test Tool Dual Hole 12V Gasoline Car Ignition Analyzer 0~6000RPM. Place the Spark Plug into tester hole 1 or 2; If you want to compare the new spark plug and old one, place new spark plug into hole 1 and the old on into hole 2.