Features: Dual Hole Testing& Time Saving: The Car Spark Plug Tester is able to dual-hole simultaneous testing as well as analog engine working, which is much more efficient and time-saving. 0 to 6000rpm Operating Frequency: The Car Spark Plug Tester is designed with adjustable working frequency, the range can reach 0 to 6000rpm. Can be adjusted as you required. Widely Application: 12V Gasoline vehicles car spark plugs, 100V-240V input voltage . Easy operation Plug And Play: Easy operation, plug and play. Come with indicator light, the status of the spark plug can be displayed more intuitively. Specifications: Item Name: Car Spark Plug Tester Power Supply100- 240V Main Unit Dimensions145x85x113mm Analog Speed0-6000rpm Operation Steps: 1.Place the spark plug in the test hole. 2..Cover the protective cover. 3.Connect the power supply,asjust the working frequency. 4.Observe the spark plug test status through the protective cover. Package Includes: 1Pcs Spark Plug Tester 1Pcs Power Supply Connector 1Pcs User Manual