Reference 2508 was introduced into the market in the mid 1930s. The first generation, such as the present watch, featured oval chronograph buttons whereas the second series were fitted with rectangular pushers.
This watch is distinguished by the beautifully aged dial and its very good original overall condition.
Different versions of reference 2508 are described and illustrated in I Cronografi Rolex - La Leggenda, Pucci Papaleo Editore, pp. 80-91.