Geekcreit Mini Digital Voltmeter Ammeter DC 100V 10A

Works as expected. Starts working at a supply voltage of 3.3V. It then draws 6.4 mA. At 5V supply the consumption is 10 mA and it remains at 10 mA up to at least 30V. Accuracy is not the best. For 3.3V with 3.3V supply voltage the error was 12%. For voltage above 4V the accuracy is about 1%, it is however trimmable by some trimpots that are accessible.