That is a very good looking Tissot! Caliber?
Type XX version??
Mathey-Tissot is actually a different company. The Swiss Jura is a pretty inbred place apparently, with the same last names popping up over and again. In any case, MT handled the assembly of the Breguet Type XX, and branded and sold a few to the public afterwards. This is one such.
That could be my first Chronograph! Have to get my Blancpain sold and wait for the prices to settle a bit but as soon as the Boutique gets them in here I want to go check it out IRL.