Calibre 671 — the 670 with 24 jewels

In brief

What the 661 is to the 660, the 671 is to the 670: the same ladies' base from the 6xx family, with the jewel count taken up to 24.

Short history

The 671 borrows more than it invents. Bridges, wheels and much of the jewelling across the whole 6xx series came out of Omega's automatic 5xx movements — cheaper to build in the 1960s, and the reason a watchmaker can now source parts from either family. Unremarkable, well made and everywhere in the Genève and De Ville of the period; the last manual calibres left the factory in 1974, with quartz already dominating the Swiss market.

Watches that used it

• Omega ladies' watch (1960s)