Review on 📊 Eiechip LED Digital Voltmeter Ammeter: Mini DC Digital Multimeter 100V 10A, Blue Red LED Amp Dual Digital Display Volt Meter Gauge for Car Current Monitoring and Testing 0.28 inch display by Tony Cole

I bought two of these for a 29.5vdc power supply I'm building. Neither of these are very accurate, but good as a reference for roughly the specified output voltage. However, one of them is buggy and reading too high, causing it to think it's over 30V when it isn't, and then turning off completely. Pretty useless actually. You can see in the picture that the meter reads 33.2V with no load when the actual voltage is 29.13V. If I increase the voltage to 29.14V, the meter's over-protection trips and turns it off.