The new Sinn 613 St And 613 St UTC Diving Chronographs

Let me give you one word that matters for the company and fans of the brand: Einsatzzeitmesser, or should I say EMZ. Now things should become a bit clearer for you, as there’s a good reason why, when looking at these new Sinn 613 St and 613 St UTC models, they might ring a bell. What we’re looking at are flipped versions of the classic EZM 13 or mission timer watch. The EZM watch by Sinn is, together with the U1 dive watch and the 104 pilot’s watch, one of its most respected and sought-after watches. The concept is now back in a fairly more classic duo, with the crown in the classic position, a day-date complication and some contrasting colours on the dial. But the main recipe of a tool watch combining functions is still there.

The original EZM 1 of 1997 was one of the cleanest and most legible diving chronographs that comes to mind. Using two central chronograph hands (for the seconds and minutes) and no sub-counters, it had a 60-minute pilot’s countdown bezel, a titanium case, and a left-sided profile with a crown and pushers at 9 o’clock. Inside was a Lemania 5100, and following the end of its production, the watch was discontinued in the late 2000s. It was originally designed for special German Customs Forces and later became available to the general public. The brand later released the EZM 3, a more classic (no chronograph) dive watch, and the EZM 13 in 2014. And in 2022, the concept came back with the EZM 13.1 Diving Chrono – the two more modern versions, however, using a different display with a 60-minute sub-dial.

The new Sinn 613 St – next to its multi-time-zone counterpart, the 613 St UTC – is essentially a flipped version of the EZM 13.1 Diving Chronograph with destro style. I’m saying essentially, as there’s a bit more than meets the eye. The overall design, specifications and dimensions remain identical. The bead-blasted, ultra-matte stainless steel case measures 41mm in diameter, 15mm in thickness and the watch head is about 98 grams. Not a small watch, but keep in mind that we’re looking at a serious aquatic tool capable of withstanding 500m of depth. The rest: sapphire crystal with double-sided AR coating; righ-positioned screw-down crown and pushers with D3-System; screwed caseback; “captive” rotating bezel (60 clicks) with black aluminium insert and 60-minute scale. A standout feature is the Ar-Dehumidifying Technology, ensuring enhanced functional reliability and freedom from fogging. Additionally, magnetic field protection up to 100 mT (80,000 A/m) effectively prevents magnetization… Classic German over-engineering – and it meets DIN 8310 and 8306 norms.

Looking at the dial, there are more modifications than on the case, yet the basics are still there. Matte black base, large painted and luminous markers, clean white lumed hands… The display of the Sinn 613 St is, however, fairly different from that of the EZM 13.1. First, the running seconds has been relocated to 9 o’clock, which incidentally leaves space for a more balanced date window at 3 o’clock (it was at 4h30), and now next to it is a day-of-the-week indication. Next, while the 60-minute sub-register is still located at 6 o’clock, it has here been white-coloured for a touch of contrast and a more modern look. The display is certainly crisp and clean, with the small seconds barely visible and used mostly at a running indicator (a necessity for a dive watch).

There is also a brand new model in the collection, the Sinn 613 St UTC Diving Chronograph. What changes here? Well, regarding the case, the specs and the overall layout of the dial; nothing. The main difference is that the day-of-the-week indication has been removed (only the date remains) and replaced by a fourth central hand that acts as a second time zone on a 24-hour basis (independently adjustable) and painted in dark grey to avoid it taking too much attention.

Both the Sinn 613 St and the 613 St UTC models run on the calibre SZ02, an internal name for modified Valjoux-based automatic chronograph movement produced by Sellita. That being said, there are some important modifications, such as the 60-minute recorder and the addition of the UTC function. These movements run at 28,800 vibrations/hour, boast 42 hours of power reserve and have a classic cam-lever chronograph mechanism. These are hidden under screwed caseback.

These two models are available on a selection of 20mm leather or silicon straps, as well as a bead-blasted stainless steel bracelet. Surely, these two new Sinn 613 St and the 613 St UTC Diving Chronographs are not revolutionary but, in all fairness, represent what Sinn does best. Solid, focused and strongly built watches for a mission. The 613 St is available now from EUR 2,450 (leather/silicon) or EUR 2,800 (steel bracelet), and the 613 St UTC from EUR 2,950 (leather/silicon) or EUR 3,300 (steel bracelet). For more details, visit www.sinn.de.