Product Parameters: Range: DC4.5-30V Reverse polarity protection, reverse does not bur Display: 2 wire 0.56 “LED digital tub Display color: Red Refresh rate: about 200mS / time Input:DC4.5-30V Resolution: 1%+1 digit Power Supply: DC4.0-30V (with the input common-line) Operating temperature: -10°C~+65°C Package Included: 1PCS Red DC4.5-30V Digital Voltmeter