We learn every day, and when it comes to the Vinage GP world, it is even more true!
While I am desperately hunting the Chronograph which inspired Girard Perregaux for the 1966 Chronograph we know, a friend came with this one:
Doesn't it sound familiar to you?
Look at this one ( the one on your right, a Type XX from Breguet ) :
A kind of Type XX from GP!
Its owner told me that this Chrono housed a Valjoux 720.
Another one to directly go to my wish list!
Best,
Nicolas