The negative is a user document half in English. The font of the text is very small so you can barely read what it says even with glasses, lacks clear content for navigating settings/modes, but if you play with it enough you should be able to figure out how to make changes to it mode or settings. I tested this with my regulated DC power supply. Barely visible but at 9 volts the screen is bright enough I slowly went from my power supply from 8 to 30 volts and this meter agreed with the report that the power meter reported an output voltage consistent with this product's LCD screen
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