BRANDS: Sinn
Sinn‘s SZ family of movement feature in-house modifications of classic movements.
The first in-house modified movement was launched in 2003. Cal. SZ01 was a modification of an ETA 7750 to make the chronograph functions easier to read for aviators or divers. If features a central 60 minute chronograph hand in addition to the existing 60-second chronograph hand, a design reminiscent of the classic Lemania 5100 movement previously used by Sinn. The company retained the running small seconds at 9 and date window at 3.
The next SZ movement, launched in 2006, was Cal. SZ02. Rather than a central chronograph minute hand, it features a 60 minute chronograph subdial, a rarely-seen feature. Designed for the model 303 World Cup Football Chronograph, this movement was made famous in the EZM 13 and EZM 13.1. These watches featured left-side crowns with running seconds at 3 and the chronograph minute subdial at 6 but no date or other functions.
That same year Sinn broke from the 7750 base, launching the Cal. SZ04 regulator on an ETA 6498 ebauche. It was a similar modification, with the hour hand moved to a subdial at 12 to offset the existing small seconds at 6 for a regulator layout. This was used in the Sinn 6100 Classic line.
Cal. SZ05, launched in 2011, gave Sinn’s 358 and 936 a classic compax look. They feature the 60 minute chronograph subdial at 3 with running seconds opposite at 9.
In 2014 Sinn introduced the 6052 Frankfurt Financial District Watch with calendar week display. It used Cal. SZ03, which was modified to feature the 60 minute chronograph seconds subdial at 12 along with day and month windows, a central pointer for the date, and a subdial at 6 showing the week number.
The SZ02 was modified for right-side crown use in 2025 in the 613 St, with the day and date windows restored. Notably, the 2025 613 St UTC Cal. SZ02 UTC adds a central 24 hour hand and drops the day window, another very unusual combination of functions.