Looks like an older analog volt-ohm meter.

I used to sell meters but not to familiar with this particular one or most analogs for that matter. The analogs aren't quite on par with some of the digital meters out there but they are by no means useless. You'll find applications for it here and there on airplanes and plenty of uses outside of RC.

What you really need for RC though is a meter that applies a slight load for checking batteries between flights. Tower sells a simple expanded scale volt meter that does this and there are some nicer, more expensive units out there as well.