✔✔✔PRODUCT PARAMETERS: - Condition: 100% Brand New; Material: Plastic + Metal; Plug: US Plug; Voltage: 100-240V. If you suspect that the spark plug is not working properly, you can compare and test it to get an accurate assessment. ✔✔✔Excellent performance: you can adjust the working frequency between 1000 rpm and 5000 rpm/min. The higher the frequency, the stronger the spark resistance. ✔✔✔Product effect: - To test the performance of the spark plug and ignition strength, apply them to spark plugs of 12V petrol vehicles. The double hole of the diagnostic tool of the spark plug analyzer of the spark plug tester can be adjusted. ✔✔✔Product features: the two-hole car spark plug tester detector has two test holes. Meanwhile, you can test two spark plugs.