3.75 x 3.75 cm. (1.5 x 1.5 in.) In 1971, Rolex introduced the brand’s last series of manually wound chronographs with the Reference 6265/63, marking the end of a decades long lineage. Improving upon ...

3.7 x 3.7 cm. (1.5 x 1.5 in.) Produced alongside references 6239 and 6241, reference 6240 was the very first Rolex chronograph to be 'truly' waterproof, with a depth rating of 100 meters, despite the ...