- Auto tester: when the engine won’t start, it helps verify if there is spark, indicating whether ignition is present. - Car spark plug detector: easy to use. Remove the rubber boot from the spark plug, insert the tester, then place the tester boot on the plug. - Car spark plug tester pen: turn the engine over; if ignition is being sent to the cylinder, the light in the tester glows. - Auto spark tester: a time-saving tool for diagnosing spark problems on cars, motorcycles, boats, chainsaws, lawn mowers, and other equipment. - Use scenario 1: diagnose a no-start car by confirming spark at the spark plug. - Use scenario 2: quick spark check for motorcycles and boats to verify ignition operation before use. - Use scenario 3: test spark on small engines such as chainsaws and lawn mowers to rule out ignition issues during maintenance.