Review on MICTUNING J0001L Waterproof 12V LED Voltmeter for Boat, Marine, Vehicle, Motorcycle, Truck, ATV, UTV, Car, Camper, Caravan - Red Digital Round Panel Display by Russell Rabbach

Excellent voltmeter. I have purchased this product in the past to control the charging system in my truck. I am planning to install a second sensor on my car. Shows the constant voltage of the charging system while driving. Much better than a dashboard that doesn't tell you if the voltage is high or low, just that you have a problem. With the sensor you know the battery and alternator status. A good battery should have 12+ volts before you start the car. If the alternator charges 14+ volts when the engine is running, there are no accessories.