Photo by Hans Koberger (CC BY 4.0), via Wikimedia Commons · Sinn 356 Flieger II, Sinn pilot-chronograph family stand-in for the 103 St Sa; both are Sinn aviation chronographs with professional-tool character.
103
Sinn’s defining aviator chronograph: the 103 family runs from the 1996 standard 103 St through the modern 103 St Sa (sapphire) with the Valjoux 7750 chronograph. The 41mm case, day-date apertures at three, and the pilot’s minute-track on the rotating inner ring are the family’s signature.
References in this family
Which ref to buy
The 103 is Sinn's classic pilot chronograph -- a 42mm Valjoux 7750-based chronograph with aviation DNA that traces back to the original Sinn 103 from the 1960s. It is the most recognizable Sinn after the U1 and the benchmark for German pilot chronographs at accessible prices.
- 1Open
Sinn 103 St Sa -- the classic pilot chronograph with TEGIMENT steel and sapphire caseback.
- The case for it:
- Valjoux 7750, 42mm, TEGIMENT hardened case, flyback-optional variants, clean three-register dial. The 103 St Sa is the fully-specified 103 -- hardened steel, sapphire caseback showing the movement, and all the Sinn engineering details. For a pilot chronograph with genuine heritage at this price, the 103 is unmatched.
- Consider instead if:
- The Valjoux 7750 is a proven movement but it is not an in-house caliber and its 7750-architecture creates a thick case profile. Buyers wanting a thinner pilot chrono should look at ETA 2894-based alternatives.
Rankings last reviewed 2026-06-07. Editorial perspective only. Not financial advice.