Fireplace vents?

What exactly are these vents above the fireplace in this picture? It is a metal firebox and the ducts angle down toward box.



Those vents simply conduct the heat (from the fireplace below) into the living area.

Exactly, those vents allow heated air to flow into the room. Typically, you will see some intake venting lower.

Thanks Larry & David. I figured as much. This is the first of it’s kind I have run across. Wanted to confirm what I figured was the purpose.