Eterna Contemporary watches

The Eterna Contemporary covers three modern lines from the Grenchen brand: the Adventic, the Avant-Garde and the Madison Eight-Days. Eterna was founded in Grenchen in 1856 by Josef Girard and Urs Schild, and its identity rests on the ball bearing: in 1948 it mounted the rotor of the Eterna-Matic on ball bearings to cut friction, and took five balls as its logo. In 2009 it came back to the idea with Spherodrive.

The Madison Eight-Days is where Spherodrive lives. It is a tonneau-shaped steel watch, 38.5 mm wide and 13.25 mm thick, built around Eterna's own hand-wound calibre 3510. Two mainspring barrels give eight days of running, shown on a power reserve indicator that balances the big date on the dial. Spherodrive is the way those barrels connect to the movement, through ball bearings that need no lubrication. The 7720.41.43.1228, 7720.41.53.1231 and 7720.41.13.1229 are the black, grey and silver-dial versions of the same watch.

The Adventic and the Avant-Garde make up the rest. The Adventic Date is a 41 mm steel watch, also made in two-tone; the Adventic GMT is the 42 mm version, and the Adventic Quartz Big Date puts a quartz movement and an oversized date in the 41 mm case. The Avant-Garde follows the same pattern at 42 mm, with a Date and a Quartz Big Date, while the Avant-Garde Lady models come at 28 and 34 mm, often with mother-of-pearl dials and two-tone cases.