Antoine Martin, the independent co-founded by Martin Braun (who formerly ran his eponymously named firm that was part of Franck Muller Watchland), has just premiered the Slowrunner, a wristwatch with both the largest, and slowest beat, balance in the world.

Equipped with a free-sprung, 24 mm diameter titanium balance wheel, the Slowrunner runs at 1 Hz or 7200 bph, a quarter the frequency of the typical 4 Hz or 28,800 bph mechanical movement. And in addition the escapement and hairspring are made of silicon. According Antoine Martin, the immense size of the balance wheel increases its inertia and stability. In theory that makes sense, the loss of inertia due to reducing the frequency can be compensated by increasing the size of the balance wheel.

Slowrunner in steel with black or silver dial

To cope with its size, the large balance is mounted on a three-armed bridge, with additional shock absorbers.

This is a fascinating idea, and its performance in real world conditions is still to be proven. The 42 mm Slowrunner is available in steel (retail CHF19,500) and rose gold (CHF34,500).