Yes mine has a shunt. It's not exactly
this model but it's close to it. The caveat is that it doesn't work well over long distances measuring current - here's why (for those that are interested).
Shunts are fantastic for measuring current, because at a given power level, there'll be a given voltage drop over the shunt. A shunt is a precisely manufactured piece of metal that has a large capacity and a very accurate resistance under load.
When a certain amount of current (amps) is passed through the shunt, the voltage drops by a certain amount. It's a tiny voltage difference. This variation is lost on the cable over about 2m. I had mine connected directly to my battery and it worked perfectly but now there's about 6m of cable from the back into the cabin I'm only getting volts - that's ok, I can tell roughly what is happening to my battery just by seeing that.
Connections are:
One side of shunt - negative battery post, along with negative wire to meter
Other side of shunt - meter sensor wire and negative out to devices
Red wire from meter - battery positive
How to tell what's happening to your battery: typically a battery that's fully charged and not being charged/floated will hold around 12.8V unless you put a load on it. If the voltage is higher than 12.8V the battery is probably being charged, and if it's less the battery is probably being discharged (or has been!).