Check the listing for details. Car Spark Plug Tester Dual Hole Plug 12V Gasoline Ignition Plug Diagnostic Tool. Condition: New. Listed at 39.99 USD. Feature:[Dual Hole Testing& Time Saving]: The LUTIFIX ST100 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 LUTIFIX ST100 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-110V 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.[2Year Warranty]: For damage caused by non-human factors, LUTIFIX promise to resend parts for free within 2 years.