Patek Philippe produced 349 examples of the reference 2499 from 1951 to 1985. The model was made in four series, the majority in yellow gold.
The first series featured square chronograph buttons, Arabic numerals and tachometer scale, the second round chronograph buttons, either baton or Arabic numerals and tachometer scale. The third, also with round buttons but simple dial with baton numerals. The fourth series (see the previous lot) resembles the third but with a sapphire crystal. In 1986 the model was replaced by reference 3970.
This watch belongs to the second series and was manufactured in 1960 and sold to the present owner on 22 October 1960.
The model is illustrated in Patek Philippe Wristwatches by Martin Huber & Alan Banbery, 2nd edition, pp. 302-304.