Small size and lightweight, convenient to carry, Easy and safe to use, no sparking 6 LED displays, clearly present the alternator and battery state. Two testing clips for safe and easy operation. Suitable for 12V lead-acid batteries, hardtop batteries, discharge batteries, and maintenance-free batteries heavy duty insulated clamps. Multiple functions- Alternator state check, battery state check, Battery overload display With a good chip inside, not easy to get hot on the surface, suitable for cars, motorcycles, etc.