Brands:Brand: Faria Beede Instruments
Chesapeake White SS 2" Voltmeter (10-16 VDC)
2" - Hole Size: 2.0625" (53mm)
A voltmeter indicates the battery voltage and the general condition of the battery charging system. The meter requires no warm-up and indicates voltage changes instantly.
It does work. And it will tell you the rough voltage. The needle is too fat and the lines are too close together to really get a good accurate voltage. Hence the reason for 4 stars, instead of five. It more or less shows whether or not you have any voltage in your battery at all.