Re: BERG LARSEN MOUTHPIECE
The numbers don't have anything to do with whether it is an alto or tenor piece.
85 is the tip opening #2 specifies baffle height and M is the facing length. Assuming the piece hasn't been modified compared to your link this has a smaller tip opening and a smaller chamber. Off the top of my head I can't tell you how similar/different the facing length and baffle are but a Berg 2 is has a pretty modest baffle which closer to the links rollover baffle than a Berg #0 or #1.