That is a Bastari english concertina, Dr Bastari and his engineers showed great ingenuity in this concertina. The reeds are probably more than acceptable as well.
That has, I believe 48 buttons, standard for treble english. I think the button linkage is mechanical and does not rely on that awful surgical tubing that later Stagi concertinas display.
Dr Bastari passed the baton to Lorenzo Stagi who made some changes in production.
I don’t know if the current line up of Stagi concertinas include a 48b english.