Feature Detection voltage DC2 5V 30VWorking current 30mADisplay 0 28 inch LEDDimensions 31 12 0 9mm length x width x height Installation hole 23 10 mmMeasurement rate ≥200mS timesAccuracy 1 1 word Red is the input positiveBlack line is the input negativePackage included 3 x Mini Digital Voltmeter