Phoneix Digital 2.50-30V Red LED Meter Voltmeter It is easy to read, install and use; and it also has Low power consumption. And it is self-powered version and supports Reverse polarity protection. You could installed it with M2.0x12 screws. When the voltage is under 10V, there will 2 readings after decimal point, which mean the accuracy is 0.01 when it is under 10V; when it is above 10v, the accuracy is 0.1. Application: Motorcycle, Car, E-bike, ATV, Scooter, 18650 battery, Li-battery and so on. Range: DC 2.5-30V two-wire access. Display: Three 0.36 "LED digital tube. Display color: Red. Refresh rate: about 500mS / times. Accuracy: 1 %(+/- 1 digit). Operating temperature: -10- 65. Size: 3.3cm x 1.5cm x 1cm - 1.3inch x 0.6inch x 0.4inch.