I don't know my measurements but I max out the protos adjustments. Have you considered the optinal XL adjuster? Swap out one part for larger sizes. I considered it for myself but decided that when my helmet starts getting too snug its time fir a haircutNo Pfanner Protos for me!
Waited for two months for back ordered on treestuff.
Just arrived and it’s tight. Also uncomfortable and the straps seem short even after adjustments.
Just wanted to have a perfect helmet and hoped that for 300$ it will work.
Now just another 20$ or so for return and my search continues.
Edit: I reread the thread and see that I'm not the first to suggest it. But maybe it'll help