Seamaster Aqua Terra 150M Co-Axial 43 GMT Stainless Steel / Red Gold / Grey / Bracelet

In Context

At 43 mm it is a large watch — well above this catalogue’s 40 mm median, and enough to dominate a narrow wrist. The case back is open, so the movement is visible without taking the watch apart, and the sapphire crystal will resist everything short of deliberate abuse. 150 m is genuine swimming resistance — more than the shape of this watch suggests it would need.

The movement winds itself from the motion of your wrist. 60 hours of reserve is enough to set it down on Friday evening and find it still running on Monday. At 28,800 vph the seconds hand advances 8 times a second.

231.20.43.22.06.003 stands on its own in this catalogue — no other reference here shares its base number. It pairs a brown dial with a red gold, stainless steel case. Beyond the time it carries a gmt.

The 8605 is the GMT version of Omega's 8500 family, a co-axial automatic with a second time zone. It sits in the Aqua Terra GMT and the Planet Ocean GMT of the mid-2010s. It powers 19 watches in this library. It adds an independently set 24-hour hand to the two-barrel [8500](/calibers/omega-8500) architecture, with a silicon Si14 balance spring, a free-sprung balance, bidirectional winding, 38 jewels and a 60-hour reserve at 29 mm across, certified by the COSC. Later examples carry the Master Co-Axial name, the anti-magnetic construction before METAS certification. The glossary explains the [GMT](/glossary/gmt) display. In the library it powers 10 [Aqua Terra](/brands/omega/aqua-terra) GMT references at 43 mm and 9 [Planet Ocean](/brands/omega/seamaster-planet-ocean) GMT references at 43.5 mm. One is a limited edition. The [8906](/calibers/omega-8906) is the Master Chronometer GMT that succeeded it, and the [8601](/calibers/omega-8601) the annual calendar on the same base.

18 other watches in the library run the Omega 8605.

Omega

Seamaster Aqua Terra 150M Co-Axial 43 GMT Titanium / White / Bracelet / GoodPlanet

231.90.43.22.04.001 · 43 mm

Omega

Seamaster Planet Ocean 600M Co-Axial 43.5 GMT Stainless Steel / Orange Numerals / Bracelet

232.30.44.22.01.002 · 43.5 mm

Omega

Seamaster Aqua Terra 150M Co-Axial 43 GMT Stainless Steel / Blue / Bracelet

231.10.43.22.03.001 · 43 mm

Omega

Seamaster Aqua Terra 150M Co-Axial 43 GMT Stainless Steel / Red Gold / Grey

231.23.43.22.06.001 · 43 mm