Help figuring out my septum size?

I had a 1.6mm in my septum, just stacked another in there so there’s now 2x 1.6mm in my septum. What gauge does this bring my septum to if I were to go with a single ring again? I’m aware that the shape of stacked vs stretched cartilage is different, this will be the maximum size I go to on my septum. Didn’t hurt nearly as much as I anticipated so that’s nice.