Versatile automotive spark plug tester that tests spark plugs and can also test other ignition components with a spark plug coil detector. Practical, well-built tool with a professional design for reliable performance and ease of use. Includes an automotive testing pen for quick testing and ignition system repair. Comes with a plug gap gauge to ensure accurate gaps and optimal performance. Broad compatibility with most automotive spark plugs and related ignition parts for diagnostics and service. Use scenarios: - In a workshop to diagnose misfires by testing spark plugs, coils, and related components. - During routine maintenance to verify plug gaps and confirm ignition system operation before replacement. - In the field or on-site to perform quick checks after installing plugs or coils, ensuring ignition operation.