About this item ★ Support short-circuit and open-circuit test, ignition system test,engine performance test, charging system test, automobile battery performance test, circuit polarity discrimination test. ★ Can detect each fault in the place where the space is narrow and light is weak.It is convenient to use, efficient to detect, easy to operate and has reliable performance. ★ Widely used in trailers, RVs, motorcycles, airplanes, snowmobiles, etc.Light tube not easy to heat and damage, durable and safe to use. ★ Professional manufacturing, high precision, high reliability, through strict quality inspection before leaving the factory, it is worth buying. ★ If you have any questions about our products, please contact us by email. Our professional customer service team will answer and solve your problems in time!