SMAKN RED 0.56" 2 Wires Waterproof LED Display Digital DC 4.0-30V Volt Voltage Panel Meter DC Voltmeter Display: 0.56" LED digital tube; Refresh rate: about 500mS / times; Range: 4.0-30V -Display Color: RED Input Polarity: DC voltage; -Measurement Accuracy:1%(+/- 1 digit). Operating temperature: -10c-65c