Patek Philippe confirm production of this watch in 1940 and its subsequent sale on January 13th, 1949.
The most distinguishing feature of this rare pocket watch is the unusual dial. It is one of very few examples produced by Patek Philippe with Arabic numerals for the odd hours (1, 3, 5, 7, 9, 11) and baton indexes for the even hours. The vertical registers further enhance this dial.
Other examples of openface chronograph watches with vertical registers are illustrated in Patek Philippe Pocket Watches by Martin Huber & Alan Banbery, p. 188.