Omega
Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph 2918.50.83
The Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph (reference 2918.50.83) is a 45.5 mm stainless steel watch with a orange dial. It is water resistant to 600 m.
Specifications
Case
- Reference
- 2918.50.83
- Collection
- Seamaster Planet Ocean
- Case size
- 45.5 mm
- Case material
- Stainless steel
- Water resistance
- 600 m
- Bracelet / strap
- Rubber
Dial and bezel
- Dial
- Orange
Movement
- Movement
- Automatic
Dial versions
This reference was made with these dials and finishes.
2918.50.83 Orange
Orange
How it compares within the Seamaster Planet Ocean family
Side by side with other references in the same collection, from the catalog.
| Reference | Size | Material | Dial | Caliber | Years |
|---|---|---|---|---|---|
| 2918.50.83 (This watch) | 45.5 mm | Stainless steel | Orange | — | — |
| 215.30.40.20.01.001 | 39.5 mm | Stainless steel | Black | 8800 | 2016– |
| 215.30.44.21.01.001 | 43.5 mm | Stainless steel | Black | 8900 | 2016– |
| 215.30.46.21.03.001 | 45.5 mm | O-MEGASTEEL | Blue gradient | 8912 | 2022– |
| 215.30.46.21.04.001 | 45.5 mm | O-Megasteel | White | — | — |
| 215.30.46.21.06.001 | 45.5 mm | O-Megasteel | Blue | — | — |
| 215.32.46.21.03.001 | 45.5 mm | O-Megasteel | Grey | — | — |
| 215.32.46.21.04.001 | 45.5 mm | O-Megasteel | White | — | — |
| 215.92.46.21.01.001 | 45.5 mm | Titanium | Black | — | — |
About the Seamaster Planet Ocean family
The Planet Ocean was introduced in 2005 as a deeper-rated Seamaster, water resistant to 600 metres, with a heavier case, a helium escape valve and bright orange accents inspired by Omega's 1960s divers.
In 2016 the line moved to Master Chronometer calibers such as the 8900, under refs. such as 215.30.44.21, and it includes GMT models, chronographs and the Deep Black models in ceramic. Case sizes vary from about 39.5 to 45.5 mm. Dealers describe a Planet Ocean by size, bezel colour and bracelet or strap, and separate the pre-2016 co-axial generation from the Master Chronometer models.
Quick answers
- What size is the Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph 2918.50.83?
- The Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph 2918.50.83 has a 45.5 mm case.
- How water resistant is the Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph 2918.50.83?
- It is water resistant to 600 metres.
- What is the Omega Seamaster Planet Ocean 600M Co-Axial 45.5 Chronograph 2918.50.83 made of?
- The case is stainless steel. Bracelet or strap: Rubber.
Catalog facts checked October 2026.