SMAKN 0.28" Digital Ammeter Voltmeter Dc 0-200v/10a Dual LED Display Red+Green Dual color display: red+green Measurement range: DC 0-200V, DC 0-10A. Resolution: 0.01V, 0.1mA(when current &lt; 1A). Refresh rate: 200ms/time. Supply voltage: DC 3.5-28V.