According to the Archives of Longines, the present watch was sold to a client in Switzerland on 30 June 1938.
This chronograph is a fine and rare examples of a stainless steel Longines "stopseconde" pilot's wristwatch. The combination of the unusual and legendary calibre 12.68 Z movement, the exceptionally beautiful original black dial and the excellent overall condition of the case render this watch exceedingly rare.
For a detailed description and illustration of this model see Longines Watches by John Goldberger, Damiani Editore, pp. 138 & 139.