It is a 2in1 Voltmeter Ammeter/Panel Meter/Monitor/Digital Meter, Power Supply: DC 4.5-30V,Measure Voltage Range DC 4.5-30V,Measure Current Range:0-100A forward current ( need extra 100A shunt for measuring current ), Accuracy: 1% (± 1 digit ),small size, high efficiency, long term stable and reliable quality,easy installation and use . Applications:LED lights measure automotive/electric cars/motorcycles battery monitoring or other products voltage current measurement.