Ravelli RV100 Classic exhaust port

[kglidd51]

Hello.

I bought a used RV100
Classic. Looking at the exhaust connection, I see a small (approx 3/8” dia) hole in the exhaust manifold. Is this for some sort of exhaust probe / sensor that it not installed?

Stove is dirty and will get a good
cleaning prior to install. 👍

Thanks.