It is a 2in1 Volt Amp Panel Meter, Power Supply: AC220V +/- 10%,Measure Voltage Range DC 0-19.99V,Measure Current Range 0-5.00(needn't external shunt,measure directly), Accuracy: 1% (± 2 digit ),small size, high efficiency, long term stable and reliable quality,easy installation and use . Applications:Suitable for Sine wave inverter, solar wind generator, LED lights measure automotive/electric cars/motorcycles battery monitoring or other products voltage current measurement.