Description: 【Function】: Spark plug tester is used to test the performance and ignition strength of spark plug, suitable for 12 V gasoline car spark plug 【High Performance】: The double hole car spark plug tester has two test holes, you can test two spark plug at the same time; the spark plug base has a larger hole of 12 mm, which is wider and compatible more spark plug 【Features】: Ignition system tester, the LED indicator is hidden to avoid dust and liquid splashing 【Spark Plug Analyzer】: With a limit fixing gasket, the spark plug is more securely connected to help better spark plug testing 【Note】: Before use, please add a gasket to ensure that the spark plug is firmly in contact (the side of the spark plug is the negative pole) Specification: Material: Metal Product Size: 165 mmx105 mmx75 mm Package Includes: 1 Spark Plug Tester(US Standard) (with Accessories) 1 European Standard Adapter Note: Please allow slightly errors 1-2cm differences due to manual measurement.