Features: Operating voltage:DC 4.5 ~ 30V Measure voltage: DC 0 ~ 100V Minimum resolution(V): 0.1V Measure current :2A (measure directly,built-in shunt) Minimum resolution(A): 0.01A Operating current: <20mA Display: three 0.28" LED digital tube Display color: Red and Blue (two-color display) Dimensions: 48 x 29 x 21mm Mounting cutout: 45.5 x 26.5mm Refresh rate: about 500mS / times Measure accuracy: 1% (± 1 digit) Operating temperature: -10 to 65° c Operating Humidity: 10 to 80% (non-condensing) Working pressure: 80 to 106 kPa Applications:Suitable for automotive/electric cars/motorcycles battery monitoring or other products voltage current measurement Wiring: Black line (thin): vacant or buck circuit (module) negative Red line (thin): power supply+ Black line (thick): COM, common measuring Red line (thick): PW+, measuring terminal voltage input positive Yellow line (thick): IN+, current input+ (Please refer to the wiring diagrams for more details) Notice: The voltage between the thin red and thin black lines must be within DC 4.5-30V The ammeter can only be connected to the negative of the device under test 10A below ammeter (include 10A), built-in shunt, does not require external shunt When the black thin line vacant, it is better to use insulating tape around the exposed part of the wire, to prevent short circuits If just be used as a voltmeter, it is recommended that the yellow line and the black line were connected together, to prevent the ammeter digital flashing Package include: 1x Digital Volt Ampere Meter