OBD DYNAMICS Dual Hole Adjustable Car Spark Plug Tester Vehicle Tool Kit

Features Car Spark Plug Tester Detector with Dual Hole Advantage: Dual Hole Car Spark Plug Tester Detector have two testing holes, you can test two spark plugs and if you suspect any spark plug works improperly you could compare and test to make an accurate judgment. Usage: Test spark plug performance and ignition strength. Application Range: 12V Petrol vehicles car spark plugs. Principle: In an automobile ignition system, the high-voltage ignition coil generates a high voltage (10000 volts or more), and the spark plug diverts its form. High-tension ignition coil in the cylinder engine, the spark between the spark plug electrodes will ignite the mixture. The Detector could tell the good spark plugs from the bad by the strength of the spark. Using Note: Please Turn Off the Power before you place the spark plug. The Spark Plug Tester is a high-voltage detector, so do not touch the spark plug with your hand at work to avoid danger.