The interior of the case-back of this old Rolex Submariner can tell us much. Clearly it is from a 5508 model, but we can also see that it was manufactured in “III.1958” which means the third quarter of 1958. Sale to the public might commonly be at least a year or two later than this. Case-backs were marked with such date stamps from the 1950s until the mid-1970s, though for most of these years a two digit year-code was used, such that a “I.72” case-back was made in the first three months of 1972. The other, hand-made scribings are service marks which can themselves be decoded. LON 1/80 92488 shows a watch visited the service division of Rolex UK in January 1980 and the job number was 92488. At Miltons we maintain an extensive database of these service dates and numbers, which prove very useful in cross-referencing watches and service histories of vintage Rolex models.