The Longines caliber 12.68Z is a vintage mechanical movement. This caliber was produced in the 1940s and 1950s.
The movement featured here was found in a vintage Longines dress watch here. This is what wahawatches said about it:
“The movement is the Longines 12.68z with serial number 9.49xxxx. On April 28th, 1956, it was sold to Bessire which was the Belgian agent for Longines at the time.
It didn’t have any problems and it kept good time. This is just a regular service to keep it in pristine condition. In the case of Longines, it’s extra important because parts are hard to find and they’re expensive.”
Longines was founded in 1832 in Saint-Imier, Switzerland. This brand is part of the Swatch Group watch conglomerate. At one point in time, Longines was manufacturing their own movements. Today, they are primarily using movements produced by the Swatch Group’s ETA factory.