Omega’s in-house caliber 8508 is a COSC rated automatic movement equipped with Co-Axial Escapement for “greater precision, stability and durability” according to Omega documentation. The picture above is from an Omega Aqua Terra 150M (126.96.36.199.01.001).
How it works:
Magnetism has always been challenging for watchmakers to deal with. Most notable about this movement is that is a entirely anti-magnetic. Until now, anti-magnetic timepieces rely on a protective case that acts as a shield layer between the movement and the case. Typically this only protects the watch from about 1000 gauss.
The caliber 8508 does not have such a container/shield, and depends on non-ferrous materials (no iron) within the parts of the movement to maintain it’s anti-magnetic status and protection of over 15,000 gauss.
This movement was developed after Swatch Group CEO G. N. Hayek requested for Omega to make their best effort in designing a completely non-magnetic watch.
As with many of Omega’s in-house movements, double barrels allow for a power reserve of 60 hours. The rotor winds in both directions to reduce winding time and is engraved with >15’000 GAUSS (1.5 tesla).
This caliber was originally announced in early 2013.
From the Omega site:
The Seamaster Aqua Terra > 15,000 gauss was the first watch to feature OMEGA’s revolutionary Co-Axial calibre 8508, which is resistant to magnetic fields greater than 15,000 gauss. This far exceeds the levels of magnetic resistance achieved by any previous watch movement and solves a problem that has always challenged watchmakers.