Protective Cover Design : Operator safety is paramount with our carefully engineered protective cover. Broad Compatibility : Compatible with a wide range of 12V gasoline engine spark plugs for versatile use. Adjustable Working Frequency : Customize the spark plug tester to simulate real-world engine conditions. Safety First Design : Enhanced with safety features to protect against electrical hazards during testing. Plug-and-Play Convenience : Quick setup and user-friendly design for seamless integration into your workflow. Transform your diagnostic skills with our Protective Cover Design Spark Tester. Perfect for automotive professionals seeking both functionality and safety, this tester features an adjustable working frequency for precise testing. With broad compatibility across 12V gasoline engines, it's a must-have tool for your arsenal, ensuring that every spark plug check is conducted with confidence and precision.