Monochrome Watches
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The New Generation of Sinn 903 St Navigation Chronograph

Sinn's classic aviation/navigation chronograph with slide rule gets refined with new lume blocks, upgraded WR and new colours.

| By Brice Goulard | 4 min read |

Founded in 1961 by former military pilot Helmut Sinn, German watchmaker Sinn has long specialised in crafting rugged sports, pilot and instrument watches with a slightly military approach. Emblematic models such as the U1 (and its smaller version, the U50), the Bundeswehr chronograph or the 103 St have forged the brand’s reputation. There’s another watch that is part of the classics, a navigation chronograph named the Sinn 903 St. This year, this watch with one of the most classic designs of the industry gets a technical update to make it even better. Here’s the new generation of 903 St. 

Before you start commenting on the fact that this watch is a copy of the Breitling Navitimer, let me explain why you’d be right on one side, but also why Sinn has the legitimacy to do so. Some might not know the story behind the creation of the Sinn 903 and why it is so close to a Navitimer in both design and technical specs. The story is that, back in the late 1970s, Breilting (like many other brands) was in a difficult situation due to the quartz crisis. Parts of Breitling were liquidated in 1979 and the rights to the Navitimer were sold to the highest bidder. This resulted in Sinn, but also Ollech & Wajs, acquiring not only the design and rights to produce a watch identical to the Navitimer (the name remained the property of Sicura, then returned to Breitling) but also stocks of parts, such as cases and dials. Sinn obtained the rights and parts of the Navitimer 806 and 809 and then produced watches under its own name with the reference 903… a model that has been in the collection for over 45 years.

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However, the Sinn 903 has evolved over the years. While it has retained many familiar traits of the Navitimer model – such as its overall design, its chronograph function and the emblematic bezel with a logarithmic scale and slide rule function – it has also gained its own identity with several upgrades. And the latest has just been presented, with a new generation of Sinn 903 St that’s all about fine-tuning a watch with excellent pedigree. Not only will Sinn offer two classic versions for the permanent collection but also a rather fancy take on its navigation chronograph with a light blue limited edition.

Visually recognisable, technically redesigned – this is what this update is all about. The case retains its classic shape with faceted lugs and a 41mm diameter. The thickness of 14.5mm can’t be hidden, but in exchange, the Navitimer-like watch gets an increased water-resistance rating of 200m or 20 bars (Navitimer watches have consistently performed poorly on this topic – the previous 903 was rated at 100m). The case is framed by sapphire crystals on both sides and features a screw-down crown. The main feature of this navigation chronograph, its continuously rotating bi-directional bezel with a logarithmic scale and slide rule function, has been kept intact and can be used to calculate times, distances or fuel consumption.

The dial, which retains the classic 3-6-9 tri-compax layout of original models, is offered in three variations: black electroplated with sunburst finishing, matte blue or, as a limited edition, sunburst light blue. All have contrasting silver-electroplated counters and inner bezels, and a date is found at 4:30 on the black and blue versions with a tone-on-tone disc. Notably, the date is absent on the light blue edition. One of the main upgrades on this new generation of Sinn 903 St is the hands and markers, which are now solid blocks made from hybrid ceramic luminous material – the markers are hand-applied on the dial, replacing the lume-painted markers. Another detail is the newly applied metallic Sinn logo.

Under the sapphire back is the same movement as the previous versions, the calibre LJP L110 produced by La Joux-Perret, an evolution of the Valjoux 7750 base now equipped with a column-wheel mechanism. This automatic chronograph movement beats at 4Hz and stores a comfortable power reserve of 60 hours. Calibre L112, the same movement without a date, powers the light blue model.

As always with Sinn, this upgraded 903 St is offered on a wide range of straps – different leathers and colours, and also silicone – as well as a classic 5-link pilot bracelet with polished and satin-finished surfaces.

Now available for orders with deliveries expected this summer, the new generation Sinn 903 St is priced at EUR 3,250 on a leather strap and EUR 3,550 on a steel bracelet… And while this watch doesn’t have the prestige of the Breitling badge and an in-house movement, I say that it is nevertheless an exciting alternative with pedigree and legitimacy at a much more accessible price and with undisputable built quality and technical specifications to match.

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4 responses

  1. Hi Brice,
    thanks for sharing this novelty by Sinn. I was not aware of the Sinn-Breitling connection, very interesting.
    You mention “solid blocks made from hybrid ceramic luminous material”, I assume you’re not talking of superluminova blocks but rather something new ?


  2. @Andrea – yes the connection is pretty interesting. As for your question, I can’t tell you more than what’s in the article, as we don’t have enough precision from the brand about it. But it seems that we’re talking about blocks that made from a luminous compound, not a coating.

  3. @Eli – the lug to lug measurement was not included in the specs but the previous versions measured 48mm in length and it seems that the case hasn’t changed much on these new ones.

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