Features: Voltmeter ammeter voltage range is AC50-500V, current range is AC1-140A. Display voltage and current simultaneously in different color, red for voltage, green for current. The monitor is powered by the circuit being measured, no need to connect extra-power source. This meter is only applicable to mains, three-phase, generators, voltage regulator and other sinewaves alternating current, not applicable to non-sinusoidal, high-frequency and voltage regulator and other occasion. If you have questions,contact us. Specifications: Material:ABS Voltage-Measuring Range: AC50-500V Current Measuring Range: AC1-140A Cable Length:Approx.18cm/7.08'' Size:Approx.45x26x14.5mm/1.77''x1.02''x0.57'' Note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x Digital Voltmeter Ammeter