340 — the Conquest's first centre-rotor automatic

In brief

Longines arrived at centre-rotor automatic winding with the 340, which went into the first generations of the Conquest and into the Flagship in its self-winding form.

Short history

Work on the 340 came as the self-winding rotor was spreading through the post-war Swiss manufactures, and Longines put forward its own engineering answer to a race that practically every major house of the period had joined.

Why it matters

Start here to follow how Longines' automatics developed, a line that carried on afterwards with higher-beat calibres such as the 290.

Watches that used it

• Longines Conquest
• Longines Flagship (automatic)