Yeeco High and Low Alarm High Precision LED Digital Voltmeter Volt Panel Meter Voltage Monitor Tester with Reverse Polarity Protection (Red) Product Features: Measuring voltage + setting alarm value Measuring range: DC3.6-50V Alarm settings: DC4.5-50V Measurement accuracy: + - 0.1V Resolution: 10V below 0.01 ,10V above 0.1V