With Rolex original fitted green presentation box and copy of Pisa Orologeria servicing invoice dated 3 May 2007.
Reference 6240 was the first "Oyster Cosmograph" model produced by Rolex. This novelty predominantly was characterized by the screw down push buttons. Reference 6240 was only in production during the second half of the 1960s and was replaced by the better known references 6263 and 6265.
This reference 6240 however is rather unusual as not fitted with the "Oyster Cosmograph" dial but with the version normally found on models without screwed pushers. According to the owner who bought the watch new over forty years ago, it never had a different dial. Albeit rather surprising given Rolex's highly standardized production in the 1960s, it shows that the first generation of Oyster Cosmographs were fitted with matching dials from the non-Oyster series.
Reference 6240 is described and illustrated in Rolex Daytona - a legend is born by Carlo Pergola, Stefano Mazzariol, Giovanni Dosso, pp. 76-92, in I Cronografi Rolex - La Leggenda, Pucci Papaleo Editore, pp. 304-311, and in 100 Superlative Rolex Watches by John Goldberger, p. 239.