Eberhard & Co. A fine and large stainless steel single button chronograph wristwatch with chronographic hack feature, multi-scale black dial and engraved case back

The extremely generous 40 mm. diameter and multi-scale dial indicate that the present watch was most probably destined to a professional market. The presence of the chronographic hack feature, a function obviously dedicated to professionals with more advanced chronographic needs, further supports this hypothesis. This feature allows the operator to interrupt the chronograph – while of course letting the rest of the watch tick. When the slide is switched back to its original place, the chronograph resumes without resetting. An Eberhard patent, it essentially provides the same functionality of a two-buttons chronograph but in a single-button movement. This model was originally launched in 1935.