Greater than 12.0 (12V CAR) OR 24.0 (24V CAR). For DC 12V or 24V Car. Between 26.0 TO 28.0 (24V CAR). Between 13.5 TO 14.5 (12V CAR). When engine running (do not drive), the LED display;. With high brightness of LED there is no difficulty in seeing the display.
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