I was pleased to see it reading properly.
I am making a volt meter control panel for my boat.
This meter has adjustment possible on the back, one for volts, I suppose other for amps and comes with the shunt.

Here are some pics showing it reading ok, compared to 2 different hand meters.

This one shows my panel I am making

I also connected to the car and it read perfect both engine off and engine on.
I hope it keeps working good like this. I have not checked the amps.
here is link to the ebay meter, meter is nice and bright. Small but easy to read.
http://www.ebay.com/itm/171460731501?_trksid=p2059210.m2749.l2649&ssPageName=STRK:MEBIDX:IT

 

I just ordered four of them the other week and they should be here today or tomorrow.

I'm planning to convert a few of my old battery chargers over to digital readouts.

 

On ebay, I found 4 sellers selling these and asked them all if they were adjustable. Only 2 responded and I bought from the one that said yes.
So I dont know if the seller who claimed no, knew anything or if they re different.
Out of the box it read ok. I did fiddle with the small pot next to the volt measuring wires and it does adjust the reading about a volt.