SMAKN 0.56" 2 Wires Blue DC 3.0v-30v LED Panel Digital Display Voltage Meter Voltmeter Measure voltage: DC 3.5-30V Measurement precision:0.01V(3-10V); 0.1V (10-30V) Display: Three 0.56" digital LED Tube Display color: BLUE Operating temperature: -10c to 65c