Openuye DC 3.2-30V LED 0.56inch Panel Meter Digital Voltmeter with Two-wire Measure Voltage: DC 3.2-30V two-wire access Display color: Red This RED DC Voltage Meter with DC3.2-30V range. It is easy to read, install and use And it is self-powered version and supports Reverse polarity protection. Highest input:DC 30V (higher than 30v has the risk of burn up)