The Certina 25-671 watch movement, produced from 1972 to 1980, is similar to caliber 1340 but lacks an additional 24-hour hand. Depending on the specific execution, it is equipped with 17 to 22 jewels. The movement features an automatic chronograph function with a 60-second, 60-minute, and 12-hour counters, which are cam switched and centered. It also includes a sub-second indicator and a quickset date feature.