In parts of the movement the following numbers and letters can be found:
CW26M; 963.116
On the battery holder:
Diameter 9,50 H 2,60
ONE JEWEL 1; UNADJUSTED SWISS
This watch would actually be found under the heading: Foreign Calibers Used By Junghans yet I would not spread further the few on this website featured Junghans quartz caliber.