CK2915-1
Speedmaster Pre-Professional Broad Arrow CK2915 — CK2915-1
First series. Metal Base 1000 bezel, broad arrow hands, oval “O” in the signature and “Speedmaster” engraved on the caseback bevel. Some bezels have a flat-topped “3”, thought to be very early. Example: movement 15,500,198, made January 1958.
One Phillips essay estimates 3,000–4,000 made. Observed movement numbers cluster around 15.49M, 15.5M, 15.99M and 16.64M.
Identifying details
- Broad arrow hands
Wide arrow-shaped hour and minute hands of the first Speedmaster.
- Steel tachymetre
Variants of CK2915
Reference overview →| Variant | Production |
|---|---|
| CK2915-1Current | 1957–1958 |
| CK2915-2 | 1958–1959 |
| CK2915-3 | 1959 |
| CK2915-3 · CK2915-3, Broad Arrow Hands | Undated |
Case & movement
- Reference
- CK2915
- Production
- 1957–1958
- Movement serials
- Case material
- Stainless steel
- Case diameter
- 38.5 mm
- Crown
- 7 mm
- Crown guards
- None
- Movement
- Manual winding
More specifications (1)
Movement
Omega 321
Hand-wound column-wheel chronograph of Lemania origin (Lemania 27 CHRO C12 / 2310 family), used by Omega from 1946 to 1968 and in every Speedmaster up to the 145.012. Early examples have a symmetrical clutch bridge; later ones an asymmetrical bridge.
Manual winding · Introduced 1946 · 18,000 vph · 17 jewels · Ø 27 mm