Working voltage of Meter: DC 4 - 30V Working current of Meter: less than or equal to 20mA Voltage Measuring range: DC 0 - 100V Current Measuring range: DC 0 - 10A Voltage resolution (V): 0.1V Current resolution (A): 0.01A Measure accuracy: 1% (1 digit) Display: 0.28 inch digital tube, two color blue and red Refresh rate: about 300ms per reading Dimensions: 48mm x 29mm x 21mm Operation Temperature: -10C to +65C Note: The maximum input voltage must not exceed 30V. Exceeding this limit may damage the meter. Color: black Material: ABS + electronic components Package Included: 2 x 0.56 inch Digital Voltmeter Ammeter DC 100V 10A Blue + Red Dual LED Display 2 x Set of two wires Content limited to the above; other items not included Note: Lighting and display differences may cause slight color variations between the image and actual item. Measurement error allowance: +/- 1-3cm