Longines, "Tre-Tacche", rare black sector dial, 35mm diameter, stainless steel, archival document included, circa late 1930s.
The stepped design & three-point screw back waterproof case, which is the origin of the name "Tre-Tacche", is a very precious gem with a case design that only Longines can provide, and the rare black sector dial with its wonderful design has a fascinating aspect of the its period. It is equipped with the famous Longines Cal. 12.68z, which has many variations such as small seconds, center seconds, and stop seconds.