Having just checked my receipt from Mike it turns out this is an M, so Cal.3130 with Breguet overcoil, larger balance wheel and full balance bridge rather than just a balance cock. Which is an entirely unexpected bonus.
Having just checked my receipt from Mike it turns out this is an M, so Cal.3130 with Breguet overcoil, larger balance wheel and full balance bridge rather than just a balance cock. Which is an entirely unexpected bonus.