Cal. 80 is a cam-switching chronograph movement produced by Hahn & Cie. of Landeron in the 1950s. It was based on Cal. 51 as part of the large Cal. 48 family, and features a full calendar like the similar Cal. 59.
Adjustment of the calendar is handled by pushers in the case:
- 1:30 – Month
- 4:30 – Date
- 10:30 – Day