Omega
Omega Speedmaster 125 ST378.0801
The Omega Speedmaster 125 (reference ST378.0801) is a 42 mm stainless steel watch. It is water resistant to 60 m. It was introduced in 1973.
Specifications
Case
- Reference
- ST378.0801
- Collection
- Speedmaster
- Case size
- 42 mm
- Thickness
- 15 mm
- Case material
- Stainless steel
- Case shape
- Round
- Crystal
- Plexi
- Water resistance
- 60 m
- Bracelet / strap
- Stainless steel
Dial and bezel
- Bezel
- Pulsometer
Movement
- Movement
- Automatic
Production
- Production
- 1973 – today (vintage)
Dial versions
This reference was made with these dials and finishes.
ST378.0801
ST378.0801 Black
Stick/dot indexes
How it compares within the Speedmaster family
Side by side with other references in the same collection, from the catalog.
| Reference | Size | Material | Dial | Caliber | Years |
|---|---|---|---|---|---|
| ST378.0801 (This watch) | 42 mm | Stainless steel | — | — | 1973– |
| 310.30.42.50.04.001 | 42 mm | Stainless steel | White | 3861 | 2024– |
| 310.92.44.50.06.001 | 44.25 mm | Grey ceramic | Grey (skeletonised) | 3869 | 2025– |
| 310.92.44.50.06.002 | 44.25 mm | Grey ceramic | Grey (skeletonised) | — | 2025– |
| 318.90.45.79.01.003 | 45 mm | Titanium | Black | 5622 | 2022– |
| 332.10.41.51.01.001 | 40.5 mm | Stainless steel | Black | 9906 | 2022– |
| 332.10.41.51.03.001 | 40.5 mm | Stainless steel | Blue | 9906 | 2022– |
| 522.30.38.50.04.001 | 38 mm | Stainless steel / ceramic | White | 3330 | 2025– |
| 522.30.38.50.04.002 | 38 mm | Stainless steel / ceramic | White | 3330 | 2025– |
About the Speedmaster family
The Speedmaster was introduced in 1957 as a sports chronograph with the tachymeter scale on the bezel. It passed NASA's tests in 1965 and was worn on the Moon in 1969, which is why the hand-wound Professional is known as the Moonwatch. Its movement has gone from the caliber 321 to the 861 and 1861, and in 2021 to the Master Chronometer 3861.
Around the Moonwatch the line includes the Speedmaster Racing, the ceramic Dark Side of the Moon, automatic chronographs, the smaller Speedmaster 38 and many special editions. Dealers check the caliber, the crystal (Hesalite or sapphire), the caseback engraving and the reference, and on vintage pieces look closely at dial, bezel and hands.
Quick answers
- What size is the Omega Speedmaster 125 ST378.0801?
- The Omega Speedmaster 125 ST378.0801 has a 42 mm case, 15 mm thick.
- How water resistant is the Omega Speedmaster 125 ST378.0801?
- It is water resistant to 60 metres.
- Is the Omega Speedmaster 125 ST378.0801 still in production?
- Vintage.
- When did the Omega Speedmaster 125 ST378.0801 come out?
- It was introduced in 1973.
- What is the Omega Speedmaster 125 ST378.0801 made of?
- The case is stainless steel. Bracelet or strap: Stainless steel.
Catalog facts checked October 2026.