Breguet Type XXI 3815 3815TI/HM/3ZU

The Type XXI is a development of the Type XX flyback chronograph. Its main difference is a central chronograph minute hand, which makes elapsed time easier to read, together with a 24-hour day-and-night indication on the dial.

The catalog lists the reference 3815 in titanium. As with the Type XX, check that the flyback function starts, resets and restarts cleanly, and that the dial and case match the reference on the papers.