1. Spark Plug Tester Using engine simulation, the automotive spark tester efficiently evaluates spark plug performance and is suitable for most 12V gasoline vehicle models. It is an ignition coil tester supporting input voltages from 100V to 240V. The ignition coil tester tool (spark tester) is almost suitable for all 12V and 24V gasoline engine spark plugs. The vehicle plug tester is compatible with 99% of crankshaft engines and motorcycle plugs, and the sparkplug tester can even be adjusted according to different plug heights. It has only reliable performance. 2. The automotive spark plug tester and coil tester are mainly used to determine the performance and ignition strength of spark plugs by comparing the spark intensity of two spark plugs, in order to identify damaged spark plugs. The spark tester automotive has two spark plug sockets. Its dual hole testing function for spark plugs allows you to simultaneously place both and old spark plugs into the testing holes, making your judgment more accurate through testing and comparison. 3. Our spark plug tool is made of high quality ABS material. The spark tester with two 12mm spark plug sockets has good impact resistance and heat resistance. The car ignition coil tester is equipped with a high voltage indicator light and a transparent protective cover. You can observe the status of the spark plug through the protective cover, ensuring during use. Attention: Be sure to cover the protective cover before use to avoid injury. 4. Spark Plug Tester with Double Test Holes Plug and play convenience. Just insert the spark plug into the spark tester and plug it in. By adjusting the RPM setting from 0 to 6000rpm, you can easily adjust the frequency by quickly turning the knob. Higher settings mean stronger sparks, simulating real engine conditions to obtain accurate readings it's that simple!