Vktech Mini Two Wires Digital Voltmeter LED Display DC2.5-30V Voltage Meter (Red Light) Two wires digital voltmeter, mini size, with reversal protection, and connect easily According to the different measuring voltage, automatically moving the position of the decimal point Operating Temperature: -10C - 65C Size: 23mm (L) x 15mm (W) Mounting Hole Center Distance: 28mm